Category Archives: Weather

On Virginia Water Radio for the Week of 10-4-21: First Frost Not Far Away

Virginia Water Radio’s episode for the week of October 4, 2021, is “Anticipating Frost as Fall Settles In.”  The 4 min./8 sec. episode, available online at http://www.virginiawaterradio.org/2021/10/episode-597-10-4-21-anticipating-frost.html, focuses on a meteorological event that’s not too far around Virginia’s corner.  This is a revised version of an episode from September 2017. The episode features a performance of “Cold Frosty Morn’” by the southwestern Virginia band New Standard.

Morning frost in Blacksburg, Va., November 29, 2020.

Virginia Water Radio, online at http://www.virginiawaterradio.org, is the Virginia Water Resources Research Center’s weekly podcast using sounds and music to focus on issues, events, people, and creatures connected to Virginia’s waters.

Virginia Water Status Report as of the End of August 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of July 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for August 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationAugust 2021 ObservedMonthly NormalSeptember 2020- August 2021 ObservedAnnual Normal based on 1991-2020
Blacksburg5.903.5749.0642.64  
Bluefield  3.893.1437.4141.24
Bristol  4.923.7645.3143.97
Charlottesville  7.263.8745.6441.61
Danville  3.163.4742.7943.73
Lynchburg  2.443.2252.5942.76
Norfolk  6.235.8852.7149.18
Reagan National Airport9.073.2556.6741.82
Richmond  7.214.9057.7645.50
Roanoke  5.393.3747.5842.82
Wallops Island  4.594.3249.3143.25
Washington-Dulles Airport4.933.5339.8343.24


The normal values used by the National Weather Service (NWS) are based on the period from 1991 to 2020, and were released on May 4, 2021.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

Location Notes
The Blacksburg location is the Blacksburg National Weather Service Office.
The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.
The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.
The Charlottesville location is the Charlottesville-Albemarle Airport.
The Danville location is the Danville Regional Airport.
The Lynchburg location is the Lynchburg Regional Airport.
The Norfolk location is the Norfolk International Airport.
Reagan National Airport is in Arlington County.
The Richmond location is the Richmond International Airport.
The Roanoke location is the Roanoke-Blacksburg Regional Airport.
The Wallops Island is in Accomack County; the location is the NASA Test Facility.
Washington-Dulles Airport is in Loudoun County.

Precipitation Sources
Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va., online at https://www.weather.gov/wrh/climate?wfo=rnk, for Blacksburg, Bluefield, Danville, Lynchburg, and Roanoke;
Morristown, Tenn., online at https://www.weather.gov/wrh/climate?wfo=mrx  for Bristol;
Baltimore-Washington, online at https://www.weather.gov/wrh/climate?wfo=lwx, for Charlottesville, Reagan-National, and Dulles;
Wakefield, Va., online at https://www.weather.gov/wrh/climate?wfo=akq,  for Norfolk, Richmond, and Wallops Island.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through August 31, 2021.


Shown below is a color-coded percentile map of monthly average stream flow values for August 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 126 Virginia sites during the 45-day period ending August 30, 2021, accessed on September 1, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.


NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 12:33 p.m. EDT on August 31, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.

Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) report of September 2, 2021, for conditions as of August 31, categorized about 28.5% of Virginia as abnormally dry or worse, and about 4.6% of the Commonwealth in moderate drought.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors for conditions as about one month, two months, three months, and one year ago:

7/29/21 – 47.2% abnormally dry or worse; 5.6% in moderate drought;

6/29/21 – 45.4% abnormally dry or worse; 5.9% in moderate drought;

5/25/21 – 98.2% abnormally dry or worse; 5.3% in moderate drought;

9/1/20 – drought-free.

Following are comments from Drought Monitor reports in August on conditions in Virginia.

From the 8/5/21 report (conditions as of 8/3/21)

“Similar to conditions in West Virginia and adjacent Maryland, abnormal dryness expanded significantly in western Virginia following several weeks of deficient rainfall, expanding into parts of western North Carolina as well.”

From the 8/12/21 report (conditions as of 8/10/21)

“Similar to conditions in West Virginia and adjacent Maryland, abnormal dryness expanded and some moderate drought was introduced in parts of central and southwestern Virginia and western North Carolina.  And similar to several other regions, isolated heavy rainfall induced small areas of improvement in central Virginia and near the Kentucky border.”

On August 6, 2021, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent report (as of 9-2-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  The DMTF’s reports typically include information from some or all of the following agencies: National Weather Service, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.

The Virginia Department of Environmental Quality produces a daily map rating drought-status indicators, online at https://www.deq.virginia.gov/water/water-quantity/drought.  Shown below is the map for August 31, 2021.  The status-indicator abbreviations on that map are as follows: GW = groundwater levels, Prcp = precipitation deficits, Res – reservoir storage, and Flow = stream flow conditions.  For each region of Virginia, the indicators are color coded for “normal,” “watch,” “warning,” or “emergency conditions.”

DROUGHT ELSEWHERE

The September 2, 2021 U.S. Drought Monitor (for conditions as of August 31) categorized about 46.5% of the United States (including parts of 40 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 30.6% of the country (including parts of 22 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country in the report for August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) for conditions in the previous three months and one year ago were as follows:

7/29/21 – 49.4% abnormally dry or worse; 32.1% severe drought or worse;

6/29/21 – 51.4% abnormally dry or worse; 29.9% severe drought or worse;

5/25/21 – 54.8% abnormally dry or worse; 25.2% severe drought or worse;

9/1/20 – 53.7% abnormally dry or worse; 20.7% severe drought or worse.

The following states had 50% or more of their land area categorized by the Drought Monitor as being in severe-or-worse drought, as of August 31:

Arizona = 54%;

California = 96 %;

Idaho = 88%;

Minnesota = 65%;

Montana = 99%;

Nevada = 95%;

New Mexico = 50%;

North Dakota = 95%;

Oregon = 99%;

South Dakota = 70%;

Utah = 100%;

Washington = 59%;

Wyoming = 61%.

Following are excerpts from Drought Monitor reports in August 2021 on conditions in various regions of the United States during summer 2021.

From the 8/5/21 report (conditions as of 8/3/21)

FROM WEST REGION SUMMARY: “This has been a region of extremes for a few weeks now. Abundant monsoonal rainfall has affected Arizona and New Mexico for about a month, and recently heavy rains expanded as far northward as eastern Nevada, southern Idaho, Utah, and the adjacent fringes of the High Plains Region. July 2021 was the wettest month ever in Tucson, Arizona, where more than 8 inches of rain fell. This stands in sharp contrast to the approximately 0.5 inch of rain that fell last July.  …Across the northern and western tiers of the West Region, conditions have been far drier, and with frequent rounds of abnormal heat, drought conditions and impacts continue to increase. Eastern Washington, central Oregon, and now parts of Montana are in Exceptional (D4) drought, with 1-classification deterioration noted across the entire state of Montana last week. The dryness and periodic intense heat have abetted the development and spread of large wildfires. So far this year, roughly the western half of the country has endured almost 17,000 large fires which have scorched about 2.5 million acres of land.”

From the 8/12/21 report (conditions as of 8/10/21)

FROM WEST REGION SUMMARY: “The dryness, exacerbated by periods of intense heat, has led to the rapid development and expansion of wildfires.  The Dixie Fire in northern California has scorched hundreds of thousands of acres, making it the second-largest fire in the state’s history.  Fires in the western half of the contiguous states (including Colorado and Wyoming) have burned, on average, 30 square miles of total area every day since early June – an area approaching half the size of Washington, DC.”

From the 8/26/21 report (conditions as of 8/24/21)

FROM MIDWEST REGION SUMMARY: “Recent dry conditions also led to expansion of moderate drought in northern Wisconsin and the Michigan Upper Peninsula.  Recent heavy rain allowed for some improvements in drought areas in Iowa and Minnesota (where the heaviest amounts occurred to alleviate very short-term dryness), but longer-term deficits and impacts to the hydrologic system remain across the greater part of the two states.  The Boundary Waters Canoe Area Wilderness in northern Minnesota closed recently due to a nearby wildfire.  The ongoing drought has also adversely affected bee populations and honey production.”

From the 9/2/21 report (conditions as of 8/31/21)

FROM NATIONWIDE SUMMARY: “In the South, Hurricane Ida made landfall along the Gulf Coast of Louisiana on Sunday [August 26] as a Category 4 hurricane with maximum sustained winds of 150 mph.  The hurricane caused extensive infrastructure damage including widespread power outages in Louisiana and Mississippi, impacting more than 1 million homes and businesses as well as stranding residents amongst the floodwaters.  In the West, dry conditions persisted across most of the region with approximately 90% of the region currently categorized as ‘in drought.’  In California, two major wildfires (Dixie and Caldor fires) continued to intensify and expand due to the dry and windy conditions. …In addition to impacting fire conditions, the on-going drought in California continues to strain the state’s water resources.  This is reflected in the reservoir levels of California’s two largest reservoirs, Lake Shasta and Lake Oroville, which are currently at 43% and 34% of historical averages, respectively.  In the Southwest, Lake Powell is currently 31% full and Lake Mead is 35% full.  The total Lower Colorado system is at 40% full, according to the U.S. Bureau of Reclamation, compared to 50% full at the same time last year.”

FROM NORTHEAST REGION SUMMARY: “According to NOAA’s National Center for Environmental Information (NCEI), July 2021 was the 2nd wettest (+2.99-inch anomaly) on record (1895–2021) for the Northeast Climate Region.”

FROM SOUTHEAST REGION SUMMARY: “According to NOAA’s NCEI, the last two-month period (June-July 2021), was the 12th wettest on record.”

FROM SOUTH REGION SUMMARY: “According to NOAA’s NCEI, the May-July 2021 period was the 4th wettest on record in the South Climate Region and the 3rd and 5th wettest May-July period statewide for Texas and Louisiana, respectively.”

FROM MIDWEST REGION SUMMARY: “According to the NOAA NCEI’s climatological rankings, the Upper Midwest Climate Region observed its 13th driest May-July period on record.”

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on August 31, 2021.

Virginia Water Status Report as of the End of June 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of July 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for July 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationJuly 2021 ObservedMonthly NormalAugust 2020- July 2021 ObservedAnnual Normal based on 1991-2020
Blacksburg6.494.2150.8442.64  
Bluefield  2.264.3637.6241.24
Bristol  4.025.0043.0043.97
Charlottesville  2.523.3747.4041.61
Danville  4.694.8845.6143.73
Lynchburg  2.474.1961.1142.76
Norfolk  2.636.0854.4749.18
Reagan National Airport4.244.3356.3341.82
Richmond  6.594.3765.8945.50
Roanoke  3.014.2846.3642.82
Wallops Island  4.974.3751.5743.25
Washington-Dulles Airport2.434.1542.5443.24

Location Notes

The Blacksburg location is the Blacksburg National Weather Service Office.

The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.

The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.

The Charlottesville location is the Charlottesville-Albemarle Airport.

The Danville location is the Danville Regional Airport.

The Lynchburg location is the Lynchburg Regional Airport.

The Norfolk location is the Norfolk International Airport.

Reagan National Airport is in Arlington County.

The Richmond location is the Richmond International Airport.

The Roanoke location is the Roanoke-Blacksburg Regional Airport.

The Wallops Island is in Accomack County; the location is the NASA Test Facility.

Washington-Dulles Airport is in Loudoun County.


Precipitation Sources

Climate pages of the following National Weather Service Forecast Offices:

Blacksburg, Va., online at https://w2.weather.gov/climate/index.php?wfo=rnk, for Blacksburg, Bluefield, Danville, Lynchburg, and Roanoke;

Morristown, Tenn., online at https://w2.weather.gov/climate/index.php?wfo=mrx, for Bristol;

Baltimore-Washington, online at https://w2.weather.gov/climate/index.php?wfo=lwx, for Charlottesville, Reagan-National, and Dulles;

Wakefield, Va., online at https://w2.weather.gov/climate/index.php?wfo=akq, for Norfolk, Richmond, and Wallops Island.

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1991 to 2020, and were released on May 4, 2021.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through July 31, 2021.

Shown below is a color-coded percentile map of monthly average stream flow values for July 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.


An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 126 Virginia sites during the 45-day period ending July 31 2021, accessed on August 1, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 7:35 p.m. EDT on August 1, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.


Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) report of July 29, 2021, for conditions as of July 27, categorized about 47.2% of Virginia as abnormally dry or worse, and about 5.6% of the Commonwealth in moderate drought.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors for conditions as about one month, two months, three months, and one year ago:

6/29/21 – 45.4% abnormally dry or worse; 5.9% in moderate drought;

5/25/21 – 98.2% abnormally dry or worse; 5.3% in moderate drought;

4/27/21 – drought-free;

7/28/20 – 43.8% abnormally dry or worse; 5.9% in moderate drought.

Following are comments from the July 29, 2021 Drought Monitor report on conditions in Virginia.

“By July 25, the U.S. Department of Agriculture reported that Virginia’s topsoil moisture was 60% very short to short, an increase of 23 percentage points from the previous week.  On the same date, pastures were rated 38% in very poor to poor condition in Virginia….”

On July 8, 2021, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent available report (as of 8-2-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  The DMTF’s reports typically include information from some or all of the following agencies: National Weather Service, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.  The DMTF was scheduled to meet again on July 29, 2021.

The Virginia Department of Environmental Quality produces a daily map rating drought-status indicators, online at https://www.deq.virginia.gov/water/water-quantity/drought.  Shown below is the map for July 30, 2021.  The status-indicator abbreviations on that map are as follows: GW = groundwater levels, Prcp = precipitation deficits, Res – reservoir storage, and Flow = stream flow conditions.  For each region of Virginia, the indicators are color coded for “normal,” “watch,” “warning,” or “emergency conditions.”

DROUGHT ELSEWHERE

The July 29 U.S. Drought Monitor report categorized about 49.4% of the United States (including parts of 38 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The July 29 report categorized about 32.1% of the country (including parts of 22 states) as being in severe drought or worse (categories D2, D3, and D4); this was the highest nationwide percentage of severe-or-worse drought since the Drought Monitor report for the week of February 7, 2013 (conditions as of February 5, 2013).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) for conditions in the previous three months and one year ago were as follows:

6/29/21 – 51.4% abnormally dry or worse; 29.9% severe drought or worse;

5/25/21 – 54.8% abnormally dry or worse; 25.2% severe drought or worse;

4/27/21 – 60.6% abnormally dry or worse; 27.1% severe drought or worse;

7/28/20 –47.8 abnormally dry or worse; 11.8% severe drought or worse.

The following states had 50% or more of their land area categorized by the Drought Monitor as being in severe-or-worse drought, as of July 27, 2021:

Arizona = 95%;

California = 95%;

Idaho = 88%;

Montana = 80%;

Nevada = 95%;

New Mexico = 67%;

North Dakota = 98%;

Oregon = 94%;

South Dakota = 71%;

Utah = 100%;

Washington = 55%;

Wyoming = 61%.

Following are Following are excerpts from Drought Monitor reports in July 2021 on conditions in the western United States during summer 2021.

From the 7/22/21 report (conditions as of 7/20/21)

FROM NATIONWIDE SUMMARY: “[A] robust monsoon circulation provided limited Southwestern drought relief, particularly in parts of Arizona, New Mexico, and southwestern Colorado.  Farther north and west, however, little or no rain fell in California, the Great Basin, and the Northwest, where dozens of wildfires were in various stages of containment.  Smoke and other particulate matter from those fires carried downwind at various atmospheric levels, producing hazy skies and reducing air quality—in some cases thousands of miles from the points of origin.”

FROM WEST REGION SUMMARY: “The Western drought continued to act on multiple time scales, ranging from a few weeks (mostly agricultural impacts) to two decades (ecological and hydrological effects).  Dozens of wildfires, primarily across northern California and the Northwest, continued to burn through hundreds of thousands of acres of timber, brush, and grass, aided by hot, dry conditions, dry soils, and ample fuels.  Wildfire smoke continued to degrade air quality in many areas of the country, well outside the West.”

From the 7/29/21 report (conditions as of 7/27/21)

FROM WEST REGION SUMMARY: “Despite the positive effect of monsoonal showers on surface conditions (e.g. improved vegetation health, topsoil moisture, and streamflow), serious long-term, underlying drought persisted, with obvious impacts on groundwater and reservoirs. The surface elevation of Lake Mead, on the Colorado River behind Hoover Dam, fell to a new record low—1,067.59 feet above sea level—on July 23. In Utah, the surface elevation of the Great Salt Lake fell below 4,191.4 feet in late July, breaking the previous record low set in 1963.”

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on August 1, 2021.

Virginia Water Status Report as of the End of June 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of June 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for June 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationJune 2021 ObservedMonthly NormalJuly 2020- June 2021 ObservedAnnual Normal based on 1991-2020
Blacksburg2.814.2746.9442.64  
Bluefield  2.724.1439.4041.24
Bristol  3.623.9245.6043.97
Charlottesville  3.284.3847.4741.61
Danville  1.203.9846.6643.73
Lynchburg  5.263.8262.3842.76
Norfolk  4.444.4354.0449.18
Reagan National Airport5.514.2058.6041.82
Richmond  4.024.6462.1045.50
Roanoke  4.374.6646.8842.82
Wallops Island  2.433.3951.1843.25
Washington-Dulles Airport3.654.3044.9643.24

Location Notes

The Blacksburg location is the Blacksburg National Weather Service Office.

The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.

The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.

The Charlottesville location is the Charlottesville-Albemarle Airport.

The Danville location is the Danville Regional Airport.

The Lynchburg location is the Lynchburg Regional Airport.

The Norfolk location is the Norfolk International Airport.

Reagan National Airport is in Arlington County.

The Richmond location is the Richmond International Airport.

The Roanoke location is the Roanoke-Blacksburg Regional Airport.

The Wallops Island is in Accomack County; the location is the NASA Test Facility.

Washington-Dulles Airport is in Loudoun County.

Precipitation Sources

Climate pages of the following National Weather Service Forecast Offices:

Blacksburg, Va., online at https://w2.weather.gov/climate/index.php?wfo=rnk, for Blacksburg, Bluefield, Danville, Lynchburg, and Roanoke;

Morristown, Tenn., online at https://w2.weather.gov/climate/index.php?wfo=mrx, for Bristol;

Baltimore-Washington, online at https://w2.weather.gov/climate/index.php?wfo=lwx, for Charlottesville, Reagan-National, and Dulles;

Wakefield, Va., online at https://w2.weather.gov/climate/index.php?wfo=akq, for Norfolk, Richmond, and Wallops Island.

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1991 to 2020, and were released on May 4, 2021.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through June 29, 2021.

Shown below is a color-coded percentile map of monthly average stream flow values for June 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 126 Virginia sites during the 45-day period ending June 29, 2021, accessed on July 1, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 3:52 p.m. EDT on June 30, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.

Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) report of July 1, 2021, for conditions as of June 29, categorized about 45.4% of Virginia as abnormally dry and about 5.9% of the Commonwealth in moderate drought.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors for conditions as about one month, two months, three months, and one year ago:

5/25/21 – 98.2% abnormally dry or worse; 5.3% in moderate drought.

4/27/21 – drought-free;

3/30/21 – 7.9% abnormally dry;

6/30/20 – 0.3% abnormally dry.

Following are comments from the Drought Monitor report of July 1, 2021 (conditions as of June 29) on conditions in Virginia.
“Intense rainfall this past week left much of the [Southeast] region virtually drought-free.  In areas that missed out on the heaviest rainfall, such as Virginia and North Carolina, pockets of moderate drought (D1) remain and areas of abnormal dryness (D0) expanded.  Rainfall deficits of 2 to 8 inches in areas of those two states still exist over the past 90 days.  State drought monitoring teams commented that [agricultural] reports continue to note moderately dry fields, which is apparent on satellite-based indicators of vegetation health, and that lake levels remain low.”

On June 25, 2021, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent report (as of 7-7-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  The DMTF’s reports typically include information from some or all of the following agencies: National Weather Service, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.

The Virginia Department of Environmental Quality produces a daily map rating drought-status indicators, online at https://www.deq.virginia.gov/water/water-quantity/drought.  Shown below is the map for June 30, 2021.  The status-indicator abbreviations on that map are as follows: GW = groundwater levels, Prcp = precipitation deficits, Res – reservoir storage, and Flow = stream flow conditions.  For each region of Virginia, the indicators are color coded for “normal,” “watch,” “warning,” or “emergency conditions.”

DROUGHT ELSEWHERE

For conditions as of June 29, 2021, the U.S. Drought Monitor categorized about 51.4% of the United States (including parts of 41 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 29.9% of the country (including parts of 24 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) for conditions in the previous three months and one year ago were as follows:

5/25/21 – 54.8% abnormally dry or worse; 25.2% severe drought or worse;

4/27/21 – 60.6% abnormally dry or worse; 27.1% severe drought or worse;

3/30/21 – 58.6% abnormally dry or worse; 24.7% severe drought or worse;

6/30/20 – 38.2% abnormally dry or worse, 8.8% severe drought or worse.

The following states had 50% or more of their land area, as of June 29, 2021, categorized by the Drought Monitor as being in severe-or-worse drought:

Arizona = 95%;

California = 95%;

Idaho = 61%;

Montana = 61%;

Nevada = 95%;

New Mexico = 85%;

North Dakota = 91%;

Oregon = 82%;

South Dakota = 69%;

Utah = 100% (99.9);

Washington = 53%;

Wyoming = 53%.

Following are Following are comments from the Drought Monitor report of July 1, 2021 (conditions as of June 29) on conditions in various parts of the United States:

High Plains: “…Producers from Wyoming eastward across the Dakotas are having to make tough decisions as to what to do with cattle, with many selling entire herds.  In response to the worsening conditions, extreme drought (D3) expanded in South Dakota and parts of Wyoming where supported by increasing rainfall deficits, declining soil moisture and streamflow, and vegetation stress.”

West: “Unprecedented heat in the Northwest, combined with another week of dry weather, led to worsening drought conditions across the region.  This week, high temperatures ranged from 20 to 30 degrees above normal, breaking multiple records.  The excess heat greatly increased evaporative demand, further drying out soils and vegetation, and worsening conditions. …Much of the West is classified as severe drought or worse.  Notable impacts include increased wildlife encounters in California, Nevada, and Utah, as drought has driven snakes and/or bears in search of food and water into urban areas in those states.  In Montana, fishing restrictions have been put in place on many rivers due to low flows and warm waters.  Drought-stricken ranchers are selling cattle due to poor forage conditions and a lack of feed.  On top of this, grasshoppers have been denuding trees and competing with cattle for food.  So far, at least eight national forests in the West now have fire restrictions.”

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on June 30, 2021.

On Virginia Water Radio for the Week of 6-7-21: The 2021 Atlantic Tropical Cyclone Season is Here

Virginia Water Radio’s episode for the week of June 7, 2021, is “Ana’s May Arrival Opens the 2021 Atlantic Tropical Cyclone Season.”  The 5 min./5 sec. episode, available online at http://www.virginiawaterradio.org/2021/06/episode-580-6-7-21-anas-may-arrival.html, is Water Radio’s annual look ahead to the Atlantic season (officially June 1-November 30) for hurricanes, tropical storms, and tropical depressions. The episode includes music composed for Virginia Water Radio by Torrin Hallett, a recent graduate of the Lamont School of Music at the University of Denver.

Predictions for the 2021 Atlantic tropical storm season.  Graphic from the National Oceanic and Atmospheric Administration, “NOAA Predicts Another Active Atlantic Hurricane Season,” 5/20/21, online at https://www.noaa.gov/media-release/noaa-predicts-another-active-atlantic-hurricane-season.

Virginia Water Radio’s is a weekly broadcast/podcast produced by the Virginia Water Resources Research Center.  The home page is http://www.virginiawaterradio.org.  Have a listen or two!

Virginia Water Status Report as of the End of April 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of April 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for April 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationApril 2021 ObservedMonthly NormalMay 2020-April 2021 ObservedAnnual Normal
Blacksburg11.973.4853.8840.89  
Bluefield2  2.243.3447.6839.63
Bristol3  1.083.3346.8741.01
Charlottesville4  2.643.3648.4242.71
Danville  1.173.4653.7744.41
Lynchburg  2.733.3163.9841.57
Norfolk  2.683.4153.4046.53
Reagan National Airport52.203.0655.3239.74
Richmond  1.343.2762.9043.60
Roanoke  2.003.3759.7441.25
Wallops Island6  2.403.0749.1240.84
Washington-Dulles Airport72.283.4746.0541.54

Location notes

1 – The Blacksburg location is the Blacksburg National Weather Service Office.

2 – The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.

3- The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.

4 – The Charlottesville location is the Charlottesville-Albemarle Airport.

5 – Reagan National Airport is in Arlington County.

6 – Wallops Island is in Accomack County.

7 – Washington-Dulles Airport is in Loudoun County.


Precipitation sources:  Climate pages of the following National Weather Service Forecast Offices:

Blacksburg, Va. (https://w2.weather.gov/climate/index.php?wfo=rnk);

Morristown, Tenn. (https://w2.weather.gov/climate/index.php?wfo=mrx);

Baltimore-Washington (https://w2.weather.gov/climate/index.php?wfo=lwx); and

Wakefield, Va. (https://w2.weather.gov/climate/index.php?wfo=akq).

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1981 to 2010.  New normals for the period of 1991-2020 were released on May 4, 2021; those normal will be used in the May 2021 edition of this monthly report.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.


For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through May 1, 2021.  Please note that the scale is different for the Virginia 30-day map.


Shown below is a color-coded percentile map of monthly average stream flow values for April 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 89 Virginia sites during the 45-day period ending April 28, 2021, accessed on April 30, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 8:43 a.m. EDT on April 30, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.

Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for April 27, 2021, categorized Virginia drought-free.  This has been the case since the week of April 13, 2021.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:

3/30/21 – 7.9% abnormally dry;

3/2/21 – drought-free;

1/26/21 – 0.02% abnormally dry;

4/28/20 – drought-free.

On November 1, 2019, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent report (as of 5-4-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  The DMTF’s reports typically include information from some or all of the following agencies: University of Virginia Climatology Office, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.

The Virginia Department of Environmental Quality uses a map rating drought-status indicators, also online at https://www.deq.virginia.gov/water/water-quantity/drought.  Shown below is the map for May 3, 2021.  The status-indicator abbreviations on that map are as follows: GW = groundwater levels, Prcp = precipitation deficits, Res – reservoir storage, and Flow = stream flow conditions.  For each region of Virginia, the indicators are color coded for “normal,” “watch,” “warning,” or “emergency conditions.”

DROUGHT ELSEWHERE

The April 27, 2021, U.S. Drought Monitor categorized about 60.6% of the United States (including parts of 45 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 27.1% of the country (including parts of 19 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) in the previous three months and one year ago were as follows:

3/30/21 – 58.6% abnormally dry or worse; 24.7% severe drought or worse;

3/2/21 – 55.0% abnormally dry or worse; 25.8% severe drought or worse;

1/26/21 – 54.7% abnormally dry or worse; 27.2% severe drought or worse;

4/28/20 – 24.0% abnormally dry or worse; 4.7% severe drought or worse.

The following states had 50% or more of their land area categorized by the April 27, 2021, Drought Monitor as being in severe-or-worse drought:

Arizona = 95%.

California = 88%.

Colorado = 60%.

Nevada = 92%.

New Mexico = 99%.

North Dakota = 93%.

Utah = 98%.

Following are comments from the April 13, 2021, Drought Monitor on severe drought conditions in parts of the United States.

From Nationwide Summary: “Parts of the Southwest are now experiencing record levels of dryness for the last 12 months. In New England, year-to-date precipitation ranks in the top 10 driest on record.

From West Regional Report: “In eastern Washington, D0 (abnormally dryness), D1 (moderate) and D2 (severe) drought expanded as precipitation deficits continued to increase, drying out soils and lowering streamflow.  Conditions once again deteriorated in Oregon this week with expansions in D2, D3 (extreme) and D4 (exceptional drought).  The warm, dry winter added to deficits that had been in place for more than a year, leaving soils extremely dry and limiting runoff.  …Drought conditions also expanded in northern and central California.  Another week without rainfall has continued to build upon longer deficits.  Cooperative Extension notes that the majority of the season’s creeks aren’t flowing and that stock ponds are still dry.  Decreases in water allocation and reduced or negligible forage are causing producers to respond by culling and selling herds.  Drought conditions are also prompting Cal Fire to bring in fire crews earlier in the season.”

Following are comments from the April 20, 2021, Drought Monitor on dry conditions in several regions of the United States.

From Nationwide Summary:

“Streamflow was well below normal all along the West Coast and in the interior West, in North Dakota and northwest South Dakota, parts of southern Texas, the southern and eastern Great Lakes, and parts of the Northeast.  Soils continued to dry out in the West and Southeast, according to U.S. Department of Agriculture (USDA) reports.  Satellite and station reports, as well as modeled indices, showed dry soils across the West, northern and southern Plains, the southern and eastern Great Lakes, and into the Northeast, as well as parts of the Southeast.  Groundwater observations from wells and estimated from satellite measurements revealed dry conditions across the West, northern and southern Plains, Northeast, and parts of the Southeast.”

Following are comments from the April 27, 2021, Drought Monitor on drought conditions in the western United States and the response by the Biden Administration to form an inter-agency working group.

From West Regional Report: “According to media reports, the Biden-Harris administration announced the formation of an Interagency Working Group to address worsening drought conditions in the West and support farmers, Tribes, and communities impacted by ongoing water shortages.  The Working Group will be co-chaired by the Departments of the Interior and Agriculture to build upon existing resources to help coordinate across the federal government, working in partnership with state, local, and Tribal governments to address the needs of communities suffering from drought-related impacts.  The Working Group will work to identify immediate financial and technical assistance for impacted irrigators and Tribes.”

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on April 30, 2021.

Virginia Water Status Report as of the End of March 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of March 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for March 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationMarch 2021 ObservedMonthly NormalApril 2020- March 2021 ObservedAnnual Normal
Blacksburg3.923.6458.1540.89  
Bluefield1  4.243.5152.0539.63
Bristol2  6.943.4453.3441.01
Charlottesville3  2.013.6652.0842.71
Danville  4.164.1157.3744.41
Lynchburg  3.173.5868.8141.57
Norfolk  1.983.6855.3146.53
Reagan National Airport43.803.4859.4239.74
Richmond  3.894.0466.2743.60
Roanoke  2.953.4663.5841.25
Wallops Island5  3.134.0050.3840.84
Washington-Dulles Airport62.273.3849.3341.54

Location notes

1 – The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.
2- The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.
3 – The Charlottesville location is the Charlottesville-Albemarle Airport.
4 – Reagan National Airport is in Arlington County.
5 – Wallops Island is in Accomack County.
6 – Washington-Dulles Airport is in Loudoun County.

Precipitation sources:  Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (https://w2.weather.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (https://w2.weather.gov/climate/index.php?wfo=mrx);
Baltimore-Washington (https://w2.weather.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (https://w2.weather.gov/climate/index.php?wfo=akq).

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1981 to 2010.  The National Climatic Data Center (now the National Centers for Environmental Information) released these normal values in July 2011.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through March 31, 2021.



Shown below is a color-coded percentile map of monthly average stream flow values for March 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 89 Virginia sites during the 45-day period ending March 30, 2021, accessed on April 1, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 1:57 p.m. EDT on April 1, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.


Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for March 30, 2021, categorized about 7.9% of Virginia as abnormally dry.  This was the first occurrence of any level of drought for Virginia since the Drought Monitor’s report of February 23, 2021.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:

3/2/21 – drought-free;
1/26/21 – 0.02% abnormally dry;
12/29/20 – drought-free;
3/31/20 – drought-free.

On November 1, 2019, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent report (as of 4-1-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  The DMTF’s reports typically include information from some or all of the following agencies: University of Virginia Climatology Office, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.

The DMTF also produces a map rating drought-status indicators, also online at https://www.deq.virginia.gov/water/water-quantity/drought.  Shown below is the map for March 31, 2021.  The status-indicator abbreviations on that map are as follows: GW = groundwater levels, Prcp = precipitation deficits, Res – reservoir storage, and Flow = stream flow conditions.  For each region of Virginia, the indicators are color coded for “normal,” “watch,” “warning,” or “emergency conditions.”

DROUGHT ELSEWHERE

The March 30, 2021, U.S. Drought Monitor categorized about 58.6% of the United States (including parts of 42 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 24.7% of the country (including parts of 19 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) in the previous three months and one year ago were as follows:

3/2/21 – 55.0% abnormally dry or worse; 25.8% severe drought or worse;
1/26/21 – 54.7% abnormally dry or worse; 27.2% severe drought or worse;
12/29/20 – 57.0% abnormally dry or worse; 28.6% severe drought or worse;
3/31/20 – 21.1% abnormally dry or worse, 2.5% severe drought or worse.

The following states had 50% or more of their land area categorized by the March 30, 2021, Drought Monitor as being in severe-or-worse drought:

Arizona = 95%.
California = 64%.
Colorado = 62%.
Nevada = 92%.
New Mexico = 99%.
North Dakota = 85%.
Utah = 97%.

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on April 1, 2021.

On Virginia Water Radio for the Week of 3-8-21: Good-bye Winter (Soon) and Thanks for the Water

Virginia Water Radio’s episode for the week of March 8, 2021, is “Spring’s Approach and the Water that Winter Left Behind.”  The 4 min./22 sec. episode, available online at http://www.virginiawaterradio.org/2021/03/episode-567-3-8-21-springs-approach-and.html, focuses on the importance of winter precipitation. The episode features music by No Strings Attached. This is a revised repeat of an episode from March 2015.

Ice hanging from a tree twig at Heritage Park in Blacksburg, Va., February 20, 2021.

Virginia Water Radio’s is a weekly broadcast/podcast produced by the Virginia Water Resources Research Center.  The home page is http://www.virginiawaterradio.org.  Have a listen or two!

Virginia Water Status Report as of the Beginning of March 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the beginning of March 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for February 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationFebruary 2021 ObservedMonthly NormalMarch 2020- Feb. 2021 ObservedAnnual Normal
Blacksburg4.352.8159.0340.89  
Bluefield1  4.662.7653.3339.63
Bristol2  4.893.4553.3341.01
Charlottesville3  5.242.7051.6042.71
Danville  4.433.0155.1744.41
Lynchburg  4.242.9368.4341.57
Norfolk  6.443.1258.5246.53
Reagan National Airport44.662.6257.9339.74
Richmond  5.122.7665.0443.60
Roanoke  4.382.8963.8741.25
Wallops Island5  6.262.7650.8940.84
Washington-Dulles Airport64.282.7449.0541.54

Location notes

1 – The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.
2- The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.
3 – The Charlottesville location is the Charlottesville-Albemarle Airport.
4 – Reagan National Airport is in Arlington County.
5 – Wallops Island is in Accomack County.
6 – Washington-Dulles Airport is in Loudoun County.

Precipitation sources:  Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (https://w2.weather.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (https://w2.weather.gov/climate/index.php?wfo=mrx);
Baltimore-Washington (https://w2.weather.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (https://w2.weather.gov/climate/index.php?wfo=akq).

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1981 to 2010.  The National Climatic Data Center (now the National Centers for Environmental Information) released these normal values in July 2011.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through March 2, 2021.

Shown below is a color-coded percentile map of monthly average stream flow values for February 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.


An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 89 Virginia sites during the 45-day period ending March 1, 2021, accessed on March 3, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 3:52 p.m. EST on March 3, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.

Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for March 2, 2021, categorized Virginia as drought-free.  This was the first drought-free categorization for Virginia since the Drought Monitor’s report of January 19, 2021.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:
1/26/21 – 0.02% abnormally dry;
12/29/20 – drought-free;
11/24/20 – drought-free;
3/3/20 – drought-free.

On November 1, 2019, the Virginia Drought Monitoring Task Force (DMTF), a collaboration of state and federal agencies, issued its most recent report (as of 3-4-21).  A link to that report, along with other current drought-status information, is available online at https://www.deq.virginia.gov/water/water-quantity/drought.  [looks like this DEQ page is under construction as of 2-1-21].  The DMTF’s reports typically include information from some or all of the following agencies: University of Virginia Climatology Office, U.S. Geological Survey (USGS), and the Virginia departments of Agriculture and Consumer Services, Health, and Environmental Quality.

DROUGHT ELSEWHERE

The March 2, 2021, U.S. Drought Monitor categorized about 55.0% of the United States (including parts of 40 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 25.8% of the country (including parts of 20 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) in the previous three months and one year ago were as follows:

1/26/21 – 54.7% abnormally dry or worse; 27.2% severe drought or worse;
12/29/20 – 57.0% abnormally dry or worse; 28.6% severe drought or worse;
11/24/20 – 58.2% abnormally dry or worse; 26.8% severe drought or worse;
3/3/20 – 20.9% abnormally dry or worse, 2.1% severe drought or worse.

The following states had 50% or more of their land area categorized by the March 2 Drought Monitor as being in severe-or-worse drought:
Arizona = 95%;
California = 57%;
Colorado = 89%;
Nevada = 92%;
New Mexico = 100% (99.9%);
North Dakota = 69%;
Utah = 97%;
Wyoming = 60%.

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on March 3, 2021.

Virginia Water Status Report as of the End of January 2021, Plus a Look at Flooding and Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, flooding, and drought, as of the end of January 2021.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.  Icons for precipitation, stream flow, groundwater, and drought are by George Wills of Blacksburg, Va. (https://www.etsy.com/people/BlacksburgArt).  For previous monthly water status reports, please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for January 2021 at 12 Virginia or near-Virginia locations, along with the “normal” (three-decade average) for this month of the year at each location.  Also shown are the precipitation totals at each location for the previous 12 months and the annual precipitation normals for each location.  The values are in inches.

LocationJanuary 2021 ObservedMonthly NormalFeb. 2020- Jan. 2021 ObservedAnnual Normal
Blacksburg3.623.0860.1040.89  
Bluefield1  3.472.9053.6139.63
Bristol2  3.573.3756.6741.01
Charlottesville3  2.042.7749.0442.71
Danville  3.573.4257.0744.41
Lynchburg  3.813.1469.5641.57
Norfolk  3.813.4056.5646.53
Reagan National Airport41.932.8156.4839.74
Richmond  3.583.0463.5143.60
Roanoke  4.182.9263.5741.25
Wallops Island5  3.523.0449.4140.84
Washington-Dulles Airport61.882.6848.0141.54

Location notes
1 – The Bluefield location is the Mercer County, W. Va., airport, near the Va.-W.Va. state line.
2- The Bristol location is the Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va./Tenn.
3 – The Charlottesville location is the Charlottesville-Albemarle Airport.
4 – Reagan National Airport is in Arlington County.
5 – Wallops Island is in Accomack County.
6 – Washington-Dulles Airport is in Loudoun County.

Precipitation sources:  Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (https://w2.weather.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (https://w2.weather.gov/climate/index.php?wfo=mrx);
Baltimore-Washington (https://w2.weather.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (https://w2.weather.gov/climate/index.php?wfo=akq).

The normal values used by the National Weather Service (NWS) in these provisional reports are based on the period from 1981 to 2010.  The National Climatic Data Center (now the National Centers for Environmental Information) released these normal values in July 2011.  For information on the normal values, see the “Climate Normals” page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the High Plains Regional Climate Center at https://hprcc.unl.edu/maps.php?map=ACISClimateMaps), where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days for all U.S. regions; or the NWS’ Advanced Hydrologic Prediction Service at http://water.weather.gov/precip/ for a map of precipitation nationwide or by state, with capability to show county boundaries, and archives available for specific days, months, or years.  Shown below are the preliminary maps from the High Plains Center of the percent-of-normal precipitation for the southeastern United States for the previous 30 days, 60 days, and 90 days, and for Virginia for the previous 30 days, all through January 31, 2021.  Please note that the scale is different for the 60-day regional map.


Shown below is a color-coded percentile map of monthly average stream flow values for January 2021 at stream gages in Virginia and just beyond the state border, compared to the historical range for each gage.  The map is from the U.S. Geological Survey (USGS) WaterWatch for Virginia, accessed online at https://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map.  The chart below the map shows the color codes/percentile classes used by USGS to compare flows to historical records for the month.

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of daily average streamflow conditions, compared to historical records for any given date.  Below is the summary plot for 89 Virginia sites during the 45-day period ending January 30, 2021, accessed on February 1, 2021, at https://waterwatch.usgs.gov/index.php?id=pa01d&sid=w__plot&r=va.

NATIONWIDE FLOODING OVERVIEW

Following is the National Weather Service’s Advanced Hydrologic Prediction Service’s (AHPS) map of stream and river levels relative to flood stage (color-coded) for the continental United States, as of 3:21 p.m. EST on February 1, 2021.  The current map is available online at http://water.weather.gov/ahps/forecasts.php; at that site, one can select Virginia or any other state of interest.

Information on current groundwater levels in Virginia monitoring wells is available from the U.S. Geological Survey’s National Water Information System, online at http://waterdata.usgs.gov/va/nwis/current/?type=gw.

DROUGHT IN VIRGINIA

The weekly U.S. Drought Monitor report from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for January 26, 2021, categorized 0.02% of Virginia as abnormally dry.  This was the Drought Monitor’s first indication of any level of drought in Virginia since the report for August 11, 2020.

Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:

12/29/20 – drought-free;
11/24/20 – drought-free;
10/27/20 – drought-free;
1/28/20 – 1.81% abnormally dry.

DROUGHT ELSEWHERE

The January 26, 2021, U.S. Drought Monitor categorized about 54.7% of the United States (including parts of 43 states plus Puerto Rico) as being abnormally dry or worse.  (The highest percentage in the abnormally or worse categories—that is, in all categories—reported by the Drought Monitor since it began in 2000 was 72.38 % of the country for the week of July 17, 2012.)  The Drought Monitor categorized about 27.1% of the country (including parts of 22 states) as being in severe drought or worse (categories D2, D3, and D4).  (The highest percentage in the severe-or-worse categories reported by the Drought Monitor since it began in 2000 was 38.48% of the country for the week of August 7, 2012.)

The nationwide percentages for abnormally dry or worse (categories D0-D4) and severe or worse (categories D2-D4) in the previous three months and one year ago were as follows:

12/29/20 – 57.0% abnormally dry or worse; 28.6% severe drought or worse;
11/24/20 – 58.2% abnormally dry or worse; 26.8% severe drought or worse;
10/27/20 – 56.0% abnormally dry or worse; 25.0% severe drought or worse;
1/28/20 – 23.9% abnormally dry or worse, 2.0% severe drought or worse.

The following states had 50% or more of their land area categorized by the January 26, 2021, Drought Monitor as being in severe-or-worse drought:

Arizona = 97%;
California = 76%;
Colorado = 91%;
Nevada = 93%;
New Mexico = 100% (99.6%);
North Dakota = 58%;
Oregon = 60%;
Utah = 98%;
Wyoming = 68%.

90-DAY DROUGHT OUTLOOK

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.php.  Shown below is the outlook map available on February 1, 2021.