Category Archives: Weather

Virginia Water Status Report as of the End of January 2016, Plus a Look at Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, and drought, as of the end of January 2016. 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, 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: Please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Precipitation Icon by George Wills

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for January 2016 at 11 Virginia or near-Virginia locations, along with the normal 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 normal annual precipitation for each location. All values are in inches.

Location January 2016

Precipitation

 

Normal for Month Feb. 2015-Jan. 2016 Precipitation

 

Normal Annual Precipitation
Blacksburg 2.44 3.08 50.14 40.89

 

Bluefield1

 

1.85 2.90 42.37 39.63
Bristol2

 

2.92 3.37 45.21 41.01
Charlottesville3

 

1.86 2.77 46.92 42.71
Danville

 

2.54 3.42 53.07 44.41
Lynchburg

 

2.77 3.14 46.21 41.57
Norfolk

 

4.62 3.40 50.62 46.53
Richmond

 

3.30 3.04 49.02 43.60
Roanoke

 

2.99 2.92 56.24 41.25
Wallops Island4

 

2.62 3.04 43.80 40.84
Washington-Dulles Airport5 4.47 2.68 40.59 41.54

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

Precipitation sources: Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (http://www.nws.noaa.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (http://www.weather.gov/climate/index.php?wfo=mrx;
Baltimore-Washington (http://www.nws.noaa.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (http://www.nws.noaa.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 released these normal values in July 2011. For information on the normal values, see the National Climatic Data Center Web page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the Southeast Regional Climate Center (Chapel Hill, N.C) at http://www.sercc.com/climateinfo/precip_maps, where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days; 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 Southeast Regional Climate Center’s preliminary maps of the percent-of-normal precipitation for the previous 30 days, 60 days, and 90 days, through January 31, 2016. Please note that the scale is different for the 30-day map.

Precipperc30

Precipperc60

Precipperc90

 Stream flow icon by George Wills

According to the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map), monthly average stream flow values for January 2016 at 154 stream gages in Virginia and just beyond the state border were in the normal range at 81% of gages, below normal at 14%, above normal at 12%, and much above normal at 3%. The color-coded, flow-percentile map for this period is shown below. The color codes/percentile classes used by USGS to compared flows to historical records for the month are shown in the chart below the map.

Streams

KEEP on deskto - Stream flow code graph

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of average streamflow conditions. Below is the summary plot for 87 Virginia sites during the 45-day period ending January 31, 2016, accessed at http://waterwatch.usgs.gov/index.php?id=pa07d&sid=w__plot&r=va on 2/1/16.

Streams graph Jan31
Water status icons groundwater by George Wills

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; and from the USGS Climate Response Network, online at http://groundwaterwatch.usgs.gov/net/ogwnetwork.asp?ncd=crn (at that page, you can find a national map showing the status of groundwater monitoring wells compared to historical values).

Drought Watch icon by George Wills
DROUGHT IN VIRGINIA

The weekly National Drought Monitor map from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for January 26, 2015, showed Virginia as drought-free. 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:
12/29/15 – 0.01% abnormally dry;
12/1/15 – 0.01% abnormally dry;
10/27/15 – 0.01% abnormally dry;
1/27/15 – 10.4% abnormally dry.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on December 14, 2015. A link to the report, along with other current drought-status information, is available online at http://www.deq.virginia.gov/Programs/Water/WaterSupplyWaterQuantity/Drought.aspx. The Task Force’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 Drought Monitoring Task Force also produces a daily map rating drought-status indicators. Shown below is daily map for February 1, 2016. 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.” Any given day’s current map and more information on drought status in Virginia are available the Task Force Web site listed above.
Drought VA Feb 1

DROUGHT ELSEWHERE

The January 26, 2016, U.S. Drought Monitor rated 25.3% of the United States (including all or parts of 33 states, plus Puerto Rico) as being abnormally dry or worse; this is the lowest nationwide percentage of abnormally dry-or-worse conditions since the week of August 3, 2010. The Drought Monitor rated 7.2% of the country (including all or parts of 6 states, plus Puerto Rico), as being in severe drought or worse (categories D2, D3, and D4); this the lowest nationwide percentage of severe-or-worse drought since the week of January 18, 2011.

The nationwide percentages for abnormally dry or worse (D0-D4) and severe or worse (D2-D4) in the previous three months and one year ago were as follows:
12/29/15 – 29.4% abnormally dry or worse; 9.7% severe drought or worse;
12/1/15 – 32.4% abnormally dry or worse; 12.3% severe drought or worse;
10/27/15 – 48.7% abnormally dry or worse; 14.4% severe drought or worse;
1/27/15 – 43.4% abnormally dry or worse; 14.1% severe drought or worse.

In California, over 86% of the state was categorized by the 1/26/16 report as being in severe-or-worse drought, with 64% in extreme or exceptional drought. The Golden State has had over 80% of its area categorized in severe-or-worse drought every week since June 25, 2013; over 90% in those categories from February 2014 to mid-December 2015; and 100% from May 13—July 29, 2014. California’s current drought began in late 2011 to early 2012.  Following are some comments from the 1/26/16 Drought Monitor on modest improvements in California from that state’s severe, multi-year, drought:

“There are finally some signs that some modest dents in the armor of the multi-year drought in California are appearing. …[C]ontinued recovery in soil moisture, long-term average streamflow, well above normal snow water content (150-180% of normal), and a trend up in reservoir levels has led to some slight improvement in the water supply situation and to the long-term drought in northern California….In what must seem like a broken record…we must stress that this doesn’t mean the region is out of drought, as many of the larger reservoirs in northern California and southern Oregon are still below half of capacity. …Relative to last year, though, the trend is going in the right direction for now with a good chunk of the snow season still left to play out over the next two months.”

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, 2016.

Drought outlook nationwide

 

 

On Virginia Water Radio for 1-25-16: Anticipating the Coming Winter Storm with Words for Snow

Virginia Water Radio’s latest episode, for the week of January 25, 2016, is Winter Word Whirlwind.  The 3 min./31 sec. episode, available online at http://www.virginiawaterradio.org/2016/01/episode-300-1-25-16-winter-word.html, gets the word on out snow from Asia to Europe to the Arctic.  The episode features “Drive the Cold Winter Away,” a traditional tune performed by Timothy Seaman of Williamsburg.

OLYMPUS DIGITAL CAMERA

Snow, ice, water, and ducks at the Virginia Tech Duck Pond, Dec. 5, 2007.

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!

East Coast Winter Storm Forecast for Jan. 21-24, 2016 – Information Resources

The latter part of the week of January 18-24, 2016, is expected to bring a significant winter storm to much of the eastern United States, with potential for heavy snowfall, power outages, and coastal flooding.

For an idea of what’s beings forecast as of 1/19/16, have a look at Weather Underground’s “East Coast Snowstorm: Five Things to Know,” online at http://www.wunderground.com/news/five-things-to-know-east-coast-snowstorm.

For an assessment of the potential for Virginia, as of 1/19/16, see “Weather Journal” by Kevin Myatt of The Roanoke Times, online at http://www.roanoke.com/weather/columns_and_blogs/blogs/weather_journal/.

For sources of information on snowfall forecasts and accumulation, please see this Virginia Water Central News Grouper post: Snowfall Prediction and Accumulation Information and Map Sources for Virginia and Nationwide, as of January 2016.

 

 

Virginia Water Status Report as of the End of December 2015, Plus a Look at Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, and drought, as of the end of December 2015. 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, 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: Please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Precipitation Icon by George Wills

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for December 2015 at 11 Virginia or near-Virginia locations, along with the normal 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 normal annual precipitation for each location. All values are in inches.

Location December 2015
Precipitation

 

Normal for Month Jan. 2015-Dec. 2015 Precipitation

 

Normal Annual Precipitation
Blacksburg 5.02 2.95 49.00 40.89

 

Bluefield1

 

3.83 2.91 42.00 39.63
Bristol2

 

5.27 3.37 44.57 41.01
Charlottesville3

 

3.83 3.15 46.76 42.71
Danville

 

5.56 3.27 52.04 44.41
Lynchburg

 

4.97 3.24 45.30 41.57
Norfolk

 

3.37 3.26 49.64 46.53
Richmond

 

5.94 3.26 49.21 43.60
Roanoke

 

4.55 2.94 54.56 41.25
Wallops Island4

 

4.28 3.43 45.94 40.84
Washington-Dulles Airport5 3.76 2.96 39.38 41.54

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

Precipitation sources: Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (http://www.nws.noaa.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (http://www.weather.gov/climate/index.php?wfo=mrx
Baltimore-Washington (http://www.nws.noaa.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (http://www.nws.noaa.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 released these normal values in July 2011. For information on the normal values, see the National Climatic Data Center Web page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the Southeast Regional Climate Center (Chapel Hill, N.C) at http://www.sercc.com/climateinfo/precip_maps, where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days; 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 Southeast Regional Climate Center’s preliminary maps of the percent-of-normal precipitation for the previous 30 days, 60 days, and 90 days, through December 31, 2015. [Please note that the scale is different for the 30-day map.]

30dPNormSERCC60dPNormSERCC90dPNormSERCC

Stream flow icon by George Wills

According to the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map), monthly average stream flow values for December 2015 at 151 stream gages in Virginia and just beyond the state border were in the normal range at 23% of gages, below normal at 1%, above normal at 38%, and much above normal at 38%. The color-coded, flow-percentile map for this period is shown below. The color codes/percentile classes used by USGS to compared flows to historical records for the month are shown in the chart below the map.

Streams DecemberKEEP on deskto - Stream flow code graph

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of average streamflow conditions. Below is the summary plot for 87 Virginia sites during the 45-day period ending December 31, 2015, accessed at http://waterwatch.usgs.gov/index.php?id=pa07d&sid=w__plot&r=va on 1/1/16.

Va stream flow 45 days as of 12-31

 

Water status icons groundwater by George Wills

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; and from the USGS Climate Response Network, online at http://groundwaterwatch.usgs.gov/net/ogwnetwork.asp?ncd=crn (at that page, you can find a national map showing the status of groundwater monitoring wells compared to historical values).

Drought Watch icon by George Wills

DROUGHT IN VIRGINIA

The weekly National Drought Monitor map from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for December 29, 2015, showed Virginia as essentially drought-free, with only 0.01 percent of the state rated as abnormally dry. 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:
12/1/15 – 0.01% abnormally dry;
10/27/15 – 0.01% abnormally dry;
9/29/15 – 39% abnormally dry;
12/30/14 – 16% abnormally dry.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on December 14, 2015. A link to the report, along with other current drought-status information, is available online at http://www.deq.virginia.gov/Programs/Water/WaterSupplyWaterQuantity/Drought.aspx. The Task Force’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 Drought Monitoring Task Force also produces a daily map rating drought-status indicators. Shown below is daily map for January 1, 2016. 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.” Any given day’s current map and more information on drought status in Virginia are available the Task Force Web site listed above.

Va Drought Jan 1

DROUGHT ELSEWHERE

The December 29, 2015, U.S. Drought Monitor rated 29.4% of the United States (including all or parts of 37 states, plus Puerto Rico) as being abnormally dry or worse. It rated 9.7% of the country (including all or parts of 9 states, plus Puerto Rico), as being in severe drought or worse (categories D2, D3, and D4; the highest percentage in these categories reported by the Drought Monitor since it began in 2000 was 38.5% of the country during the week of August 7, 2012).

The nationwide percentages for abnormally dry or worse (D0-D4) and severe or worse (D2-D4) in the previous three months and one year ago were as follows:
12/1/15 – 32.4% abnormally dry or worse; 12.3% severe drought or worse;
10/27/15 – 48.7% abnormally dry or worse; 14.4% severe drought or worse;
9/29/15 – 53.0% abnormally dry or worse; 16.8% severe drought or worse;
12/30/14 – 39.2% abnormally dry or worse; 14.1% severe drought or worse.

In the following states, over 50% of the state was categorized by the 12/29/15 report as being in severe-or-worse drought.

California – 88% (with 69% in extreme or exceptional drought). This is the lowest percentage of severe-or-worse drought in California since December 2013. The Golden State has had over 80% of its area categorized in severe-or-worse drought every week since June 25, 2013; over 90% in those categories from February 2014 to mid-December 2015; and 100% from May 13—July 29, 2014. California’s current drought began in late 2011 to early 2012.

Nevada – 65% (with 32% in extreme or exceptional drought). Nevada has had over 50% of its area in severe-or-worse drought since the week of March 27, 2012.

Oregon – 65% (with 61% in extreme drought). Oregon had 100% of its area categorized in severe-or-worse drought from the week of July 28, 2015, through the week of October 27, 2015.

Following are some comments from the 12/29/15 Drought Monitor on some notable conditions or events in various parts of the country, particularly as a result of a large storm system that affected much of the country during the week of December 23-29, 2015.

Nationwide
“A large complex storm system produced copious amounts of precipitation in the Central and Southern US during this….week. The seasonably cold air behind the system mixed with the unseasonably warm, moist air that was entrenched across the east. This produced an unstable air mass kicking off heavy rains, thunderstorms, blizzards, tornadoes and historic flooding. …The 7-day precipitation totals amounted to 800 percent of normal or greater for a large swath stretching from eastern Oklahoma, northwest Arkansas, much of Missouri, and Illinois. Portions of Alabama and Georgia also recorded far greater than normal precipitation amounts. …Average temperature departures were in the range of 20-25 degrees above normal for the…week. Temperature anomalies were as much as 20 degrees below normal in the western third of the country. The following is a list of preliminary daily and monthly temperature data records that were tied or broken during the period from December 23 – 29: 1926 highest daily maximum temperatures; 2019 highest daily minimum temperatures [including 64 degrees F at Danville, Va., 18 degrees above the previous daily record minimum for that date]; 59 highest monthly maximum temperatures; 240 highest monthly minimum temperatures.”

 Central
“As the storm moved northeastward, a mixture of rain and blizzard like conditions affected the Central region. Heaviest rain amounts were in Missouri and Illinois where much of the area received at least 5 inches or more. Historic flooding was a concern along the banks of the Mississippi. In St Louis, the river was expected to crest at 44.8 feet – its second highest level ever recorded – only behind the great flood of 1993.”

South
“The massive storm system brought heavy snows in New Mexico and West Texas. According to storm reports, snow totals topped out at 41” in New Mexico and 24” in Texas. Severe weather affected East Texas dumping in excess of 10 inches of rain in the region. Violent tornadoes, some rated as high as EF4, caused extensive damage and loss of life.Oklahoma bore the brunt of the precipitation where the eastern portion of the state received as much as 11 inches of rain in a 3-day period. For some areas, the wet December bolstered the annual totals, topping the wettest calendar year on record for the state of Oklahoma.”

West
The relentless flow of moisture has benefited the drought stricken areas of the Northwest and West Coast. …For December, precipitation in northwest California was 150-300 percent of normal. …[W]hile the improvements along the coast are evident, they have not been seen inland, yet. Further south, the recent storms have dried out as they moved south into the Monterey [California] area. …In Los Angeles, much like Monterey, all precipitation locations are below normal for the current water year as nearly all of the storm systems have weakened as they approach the area. Reservoirs in San Diego remained unchanged as most of the recent rains soaked into the ground. In Sacramento recent storms have helped with local precipitation totals, and are finally beginning to generate runoff, but not enough to warrant changes in the drought status.”

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 January 1, 2016.

Drought outlook map avail as of 1-1-16

Preliminary Tornado and Other Severe Weather Maps for Dec. 26-27, 2015, from NWS/Storm Prediction Center

Below are the National Weather Service/Storm Prediction Center’s maps of preliminary (not yet verified) reports of high winds, hail, and tornadoes in the continental United States on December 26 and 27, 2015, including fatal tornadoes in Texas.  (For two news accounts, see “What’s stirring up this winter’s extreme storms?,” PBS NewsHour, 12/28/15; and Texas under siege: Tornadoes, flooding, snow, and ice,” USA Today, 12/27/15).

The Storm Prediction Center’s daily storm-report maps and notes are available online at http://www.spc.noaa.gov/climo/online/.  From that link, you can also access the Center’s archive of maps and reports going back several years.

Severe weather reports Dec26 2015

Severe weather reports Dec27 2015

 

Salt Marsh Erosion in Coastal Areas of the United States, Australia, and Italy Seen to be Resulting from Frequent, Moderate Storms, according to Research Published in December 2015

Recently published research at eight salt marsh locations in the United States, Australia, and Italy indicates that most of the marsh erosion at those locations is due to wave action in frequent, moderate storm events (those that occur about every two to three months), rather than in rare, catastrophic storms, such as Superstorm Sandy along the eastern U.S. coast in 2012.   The findings are in research published in December 2015 by scientists at Boston University and the U.S. Geological Survey (USGS) in Woods Hole, Mass.

According to the study’s abstratct, the study’s result “clearly shows that long-term salt marsh deterioration is dictated by average wave conditions, and it is, therefore, predictable.  Violent storms and hurricanes contribute less than 1% to long-term salt marsh erosion rates.  This result is of high value for coastal restoration projects and the use of living shorelines to mitigate storms effect.”

The study is “A linear relationship between wave power and erosion determines salt-marsh resilience to violent storms and hurricanes,” by Nicoletta Leonardi, Neil K. Ganju, and Sergio Fagherazzi, in Proceedings of the National Academy of Sciences.  A Dec. 21, 2015, USGS news release on the study is available online at this link.

Virginia Water Status Report as of the End of November 2015, Plus a Look at Drought Nationally

Here is the Virginia Water Central News Grouper’s monthly water-status report on precipitation, stream flow, and drought, as of the end of November 2015. 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, 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: Please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

 

Precipitation Icon by George Wills

Here are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for November 2015 at 11 Virginia or near-Virginia locations, along with the normal 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 normal annual precipitation for each location. All values are in inches.

Location November 2015

Precipitation

 

Normal for Month Dec. 2014-Nov. 2015 Precipitation

 

Normal Annual Precipitation
Blacksburg 4.13 2.87 46.63 40.89

 

Bluefield1

 

2.92 2.69 40.56 39.63
Bristol2

 

3.70 3.10 42.33 41.01
Charlottesville3

 

2.82 3.83 45.72 42.71
Danville

 

6.06 3.36 49.15 44.41
Lynchburg

 

4.39 3.41 43.45 41.57
Norfolk

 

4.62 3.15 49.97 46.53
Richmond

 

3.91 3.24 46.41 43.60
Roanoke

 

4.00 3.40 52.55 41.25
Wallops Island4

 

3.84 2.87 44.88 40.84
Washington-Dulles Airport5 2.06 3.41 38.88 41.54

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

Precipitation sources: Climate pages of the following National Weather Service Forecast Offices:
Blacksburg, Va. (http://www.nws.noaa.gov/climate/index.php?wfo=rnk);
Morristown, Tenn. (http://www.weather.gov/climate/index.php?wfo=mrx;Baltimore-Washington (http://www.nws.noaa.gov/climate/index.php?wfo=lwx); and
Wakefield, Va. (http://www.nws.noaa.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 released these normal values in July 2011. For information on the normal values, see the National Climatic Data Center Web page at http://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals.

For graphs of precipitation, visit the Southeast Regional Climate Center (Chapel Hill, N.C) at http://www.sercc.com/climateinfo/precip_maps, where you can find maps of total precipitation and percent of normal precipitation for the past 7, 30, 60, or 90 days; 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 Southeast Regional Climate Center’s preliminary maps of the percent-of-normal precipitation for the previous 30 days, 60 days, and 90 days, through November 30, 2015.

Precip perc 30 day

Precip perc 60 day

Precip perc 90 day

 

Stream flow icon by George Wills According to the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/index.php?m=mv01d&r=va&w=map), monthly average stream flow values for November 2015 at 150 stream gages in Virginia and just beyond the state border were in the normal range at 50% of gages, below normal at 2%, above normal at 25%, and much above normal at 23%. The color-coded, flow-percentile map for this period is shown below. The color codes/percentile classes used by USGS to compared flows to historical records for the month are shown in the chart below the map.

Streams November

KEEP on deskto - Stream flow code graph

An overall look at Virginia streamflow conditions is provided in the USGS WaterWatch summary plot of average streamflow conditions. Below is the summary plot for 87 Virginia sites during the 45-day period ending November 29, 2015, accessed at http://waterwatch.usgs.gov/index.php?id=pa07d&sid=w__plot&r=va on 12/1/15.

Stream graph
Water status icons groundwater by George Wills

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; and from the USGS Climate Response Network, online at http://groundwaterwatch.usgs.gov/net/ogwnetwork.asp?ncd=crn (at that page, you can find a national map showing the status of groundwater monitoring wells compared to historical values).

Drought Watch icon by George Wills DROUGHT IN VIRGINIA

The weekly National Drought Monitor map from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for December 1, 2015, showed Virginia as essentially drought-free, with only 0.01 percent of the state rated as abnormally dry. 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:
10/27/15 – 0.01% abnormally dry;
9/29/15 – 39% abnormally dry;
8/25/15 – 7% abnormally dry;
12/2/14 – 33% abnormally dry.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on October 13, 2015. A link to the report, along with other current drought-status information, is available online at http://www.deq.virginia.gov/Programs/Water/WaterSupplyWaterQuantity/Drought.aspx. The Task Force’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 Drought Monitoring Task Force also produces a daily map rating drought-status indicators. Shown below is daily map for December 1, 2015. 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.” Any given day’s current map and more information on drought status in Virginia are available the Task Force Web site listed above.

Drought VA Dec1DROUGHT ELSEWHERE

The December 1, 2015, U.S. Drought Monitor rated 32.4% of the United States (including all or parts of 40 states, plus Puerto Rico) as being abnormally dry or worse. It rated 12.3% of the country (including all or parts of 9 states, plus Puerto Rico), as being in severe drought or worse (categories D2, D3, and D4; the highest percentage in these categories reported by the Drought Monitor since it began in 2000 was 38.5% of the country during the week of August 7, 2012).

The nationwide percentages for abnormally dry or worse (D0-D4) and severe or worse (D2-D4) in the previous three months and one year ago were as follows:
10/27/15 – 48.7% abnormally dry or worse; 14.4% severe drought or worse;
9/29/15 – 53.0% abnormally dry or worse; 16.8% severe drought or worse;
8/25/15 – 49.2% abnormally dry or worse; 15.1% severe drought or worse;
12/2/14 – 40.7% abnormally dry or worse; 14.3% severe drought or worse.

In the following states, over 50% of the state was categorized by the 12/1/15 report as being in severe-or-worse drought.

California – 92% (with 71% in extreme or exceptional drought). California has had over 80% of its area categorized in severe-or-worse drought every week since June 25, 2013, and the Golden State had 100% in those categories from May 13—July 29, 2014. California’s current drought began in late 2011 to early 2012.

Nevada – 66% (with 32% in extreme or exceptional drought). Nevada has had over 50% of its area in severe-or-worse drought since the week of March 27, 2012.

Oregon – 90% (with 61% in extreme drought). Oregon had 100% of its area categorized in severe-or-worse drought from the week of July 28, 2015, through the week of October 27, 2015.

Washington – 60% (with 45% in extreme drought).

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 December 1, 2015.

Drought US Outlook Nov19