Category Archives: Weather

September 2015 is National Preparedness Month in Virginia

On September 2, 2015, Virginia Governor Terry McAuliffe proclaimed September as National Preparedness Month in Virginia.  The timing of this campaign coincides with the start of what’s historically been the most active part of the Atlantic tropical storm season—the months of September and October. Below are the hyperlinked headline and an excerpt from the governor’s office’s September 2 news release.  Also, for two audio takes on preparedness for tropical storm season, please see these Virginia Water Radio episodes:
Here Comes Atlantic Tropical Storm Season 2015 (week of 5-8-15);
“Natural Disaster” by John McCutcheon Helps Spin Out a Reminder about Tropical Storm Season (week of 8-11-14).

Governor McAuliffe Declares September as Preparedness Month in Virginia, Virginia Governor’s Office News Release, 9/2/15.

Excerpt: “Governor Terry McAuliffe has proclaimed September as National Preparedness Month in Virginia and he encourages business owners, families and communities to be ready for emergencies. … Everyone can prepare for all emergencies, including hurricanes, by taking these steps:
*Sign up for text alerts/weather warnings that may be offered by your locality.
*Download the free Ready Virginia app for iPhone® and Android™.
*Have basic supplies on hand to last at least three days for each family member:
**Food that won’t spoil, such as canned and packaged foods.
**Water, one gallon per person per day.
**A working battery-operated radio and extra batteries.
**Flashlights with extra batteries.
**First aid kit.
**A written list of your prescriptions and prescribing doctor(s) and at least a week’s supply of medications.
**Food and water for your pets.

*Create a family emergency communications plan:
**Decide how and where everyone will meet up with each other if separated.
**Choose an out-of-town emergency contact for your family and give that person’s phone number to each family member.
**Make a sheet of emergency contacts and post it in visible places in your home and workplace.  Don’t rely on your smart phone or online contact lists.
**Get a free emergency plan worksheet and emergency contact cards at www.ReadyVirginia.gov or *www.ListoVirginia.gov or use the new Ready Virginia app.

People with disabilities or access and functional needs may need to take additional steps.  Plan how to handle power outages and/or being asked to evacuate.  For more information, visit www.vaemergency.gov/readyvirginia/getakit/disabilities.

Virginia Water Status Report as of the End of August 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 August 2015. T  he 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 WillsHere are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for August 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 August 2015
Precipitation

 

Normal for Month Sept. 2014-Aug 2015 Precipitation

 

Normal Annual Precipitation
Blacksburg 4.09 3.59 40.89 40.89
Bluefield1 2.39 3.26 39.18 39.63
Bristol2 6.01 3.47 42.25 41.01
Charlottesville3 2.43 3.62 37.50 42.71
Danville 3.06 3.97 41.70 44.41
Lynchburg 1.98 3.26 35.48 41.57
Norfolk 1.85 5.52 51.00 46.53
Richmond 2.77 4.66 42.76 43.60
Roanoke 3.09 3.56 42.28 41.25
Wallops Island4 2.67 4.19 41.52 40.84
Washington-Dulles Airport5 1.09 3.53 37.14 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 August 31, 2015.

30 Day Precip Perc60 day precip perc90 day precip perc 

Stream flow icon by George Wills

According to the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/classic.php?m=mv01d&r=va&w=real%2Cmap), monthly average stream flow values for August 2015 at 131 stream gages in Virginia and just beyond the state border were in the normal range at about 71% of gages, below normal at about 27%, and above normal at about 2%. 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 AugustKEEP on deskto - Stream flow code graph 

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 August 25, 2015, showed Virginia as having about 7% of its area as abnormally dry, located in several localities along the North Carolina border in southeastern Virginia. This was the first report of any drought in Virginia since the Drought Monitor for June 30, 2015. The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.” Drought Monitor categories are as follows:
D0 = abnormally dry;
D1 = moderate drought;
D2 = severe drought;
D3 = extreme drought;
D4 = exceptional drought.

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:
7/28/15 – drought-free;
6/30/15 – 13% abnormally dry;
5/26/15 – 32% abnormally dry;
8/26/14 – 9% abnormally dry.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on July 16, 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 next report is scheduled for September 2015. 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 the map for August 31, 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 Virginia Aug 31

MORE ON GROUNDWATER LEVELS

More 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 ELSEWHERE

 The August 25, 2015, U.S. Drought Monitor rated 49.2% of the United States (including all or parts of 44 states, plus Puerto Rico) as being abnormally dry or worse. It rated 15.1% of the country (including all or parts of 18 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:
7/28/15 – 44.2% abnormally dry or worse; 14.4% severe drought or worse;
6/30/15 – 41.7% abnormally dry or worse; 13.0% severe drought or worse;
5/26/15 – 46.4% abnormally dry or worse; 11.9% severe drought or worse;
8/26/14 – 39.9% abnormally dry or worse; 18.0% severe drought or worse.

In the following states, over 50% of the state was categorized by the 8/25/15 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. Here’s a link to an Associated Press story on how the drought has led to an increase in land subsidence, resulting in significant increased costs to roads and other infrastructure: California land quickly sinking in drought costs farmers, 8/20/15.

Nevada – 76% (with 38% 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 – 100% (with 67% in extreme drought).

Washington – almost 100% (with 85% in extreme drought).

Oregon and Washington have had 100% of their area (99.99% in the case of Washington) in severe-or-worse drought since the week of July 28, 2015.

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.html. Shown below is the outlook map available on September 1, 2015.

Drought Outlook US Aug

August 2015 Atlantic Tropical Storm Summary from the National Hurricane Center Issued September 1, 2015

On September 1, 2015, the National Hurricane Center (NHC) issued its monthly tropical weather summary for August 2015 for the North Atlantic, Caribbean Sea, and Gulf of Mexico; the report is available online at http://www.nhc.noaa.gov/text/MIATWSAT.shtml (as of 9/1/15).

Three tropical cyclones—Major Hurricane Danny (a “major hurricane” is Category 3 or higher), Tropical Storm Erika, and Hurricane Fred—formed in the basin in August.  According to the NHC’s September 1 report, records from 1981—2010 indicate that on average one named storm forms in the Atlantic basin in August every year, and a hurricane forms in August about once every other year.  The September 1 report also notes that, “in terms of Accumulated Cyclone Energy (ACE), which measures the combined strength and duration of tropical storm and hurricanes, activity in the Atlantic basin so far in 2015 has been below normal.”

Below is the NHC’s list of all tropical depressions, tropical storms, and hurricanes this year through August, with their dates of occurrence and maximum wind speeds, and the Center’s graph of preliminary tracks (subject to verification) of Atlantic tropical storms and hurricanes in 2015, as of 9-1-15.  Abbreviations: H = hurricane; MH = major hurricane; TD = tropical depression; TS = tropical storm.

TS Ana – May 8-11 – 60 mph
TS Bill – June 16-20 – 60 mph
TS Claudette – July 13-14 – 50 mph
MH Danny – August 18-24 – 115 mph
TS Erika – August 25-29 – 50 mph
H Fred – August 30 to present, as of 9/1/15 – 85 mph

Tropical Storms through August

When reports on individual storms in 2015 are completed, the reports (including maps of tracks) will be available online at http://www.nhc.noaa.gov/data/tcr/index.php?season=2015&basin=atl.

For a discussion of the Atlantic tropical storm season so far, including the apparent impacts of an El Nino occurrence this year, please see Weather Journal: Hurricane season going by El Nino playbook, by Kevin Myatt, Roanoke Times, 9/2/15.

For previous News Grouper posts on tropical storm monthly and yearly reports from the National Hurricane Center, please go to this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Monthly+Tropical+Storm.

Erika photo

Satellite photo of Tropical Storm Erika (lower right corner of photo), east of the Caribbean Sea’s Leeward Islands on August 26, 2015, 8:15 a.m. EDT (1215 Z, or Greenwich Mean Time). Photo taken from the National Oceanic and Atmospheric Administration (NOAA) Web site, http://www.goes.noaa.gov/browsh.html, on 8/26/15.

Virginia Precipitation and Stream Flow for the 7-day Period Ending August 25, 2015

Below are images showing precipitation in Virginia and other areas of the southeastern United States, and stream flow in Virginia, over the seven-day period ending August 25, 2015.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing precipitation and stream-flow information and images.

For monthly reviews of precipitation, stream flow, and drought, please see the News Grouper posts available at this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Monthly+Water+Status.

For more information on current and historical surface-water and groundwater conditions in Virginia, please see the U.S. Geological Survey (USGS) Virginia Science Center’s Web site, http://va.water.usgs.gov/.

Precipitation

The following maps show southeastern U.S. precipitation amounts (top map) and the percent of normal precipitation for the given location at this time of year (bottom map) over the seven-day period ending August 25, 2015.  The maps were accessed on 8/26/15 from the National Oceanic and Atmospheric Administration’s (NOAA) Southeast Regional Climate Center, located at the University of North Carolina in Chapel Hill; online at http://www.sercc.com/climateinfo/precip_maps.  As of that date, these data were provisional (needing to be verified for accuracy and subject to possible revision).

Precip Aug25Precipperc Aug25

Another source of precipitation data is the National Weather Service’s Advanced Hydrologic Prediction Service, http://water.weather.gov/precip/, provides maps showing precipitation nationwide or by state for specific days, months, or years. The site also has the capability to show county boundaries.  Shown below are U.S. maps of precipitation and percent of normal precipitation for the 7-day precipitation ending at 8 a.m. Eastern Daylight Time on August 26, 2015.  (Please note that UTC, the time shown on the map below, is five hours ahead of Eastern Standard Time and four hours ahead of Eastern Daylight Time.)
PRecip US
precip perc US

Stream Flow

Average Virginia stream flow over the seven-day period ending August 25, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia, accessed online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap on 8/26/15.  The map’s color-coded dots compare the previous week’s average stream flows to the normal flow levels for that week over the historical record for each gaging station.  The “bluer” the color of the dots, the higher the percentile and flow relative to normal for the site and time of year; the “redder” the dots, the lower the percentile and flow relative to normal.  The color codes/percentile classes used by USGS are as shown in the chart following the map.

Streams Aug 25KEEP on deskto - Stream flow code graph

Virginia Precipitation and Stream Flow for the 7-day Period Ending August 18, 2015, Plus a Mid-Month Drought Assessment

Precipitation (online, do as Heading 4, bold, darkest blue color)

Below are images showing precipitation in Virginia and other areas of the southeastern United States, and stream flow in Virginia, over the seven-day period ending August 18, 2015.  Also below is a map showing the status of several drought indicators in different Virginia regions, as of August 19.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing precipitation and stream-flow information and images.

For monthly reviews of precipitation, stream flow, and drought, please see the News Grouper posts available at this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Monthly+Water+Status.

For more information on current and historical surface-water and groundwater conditions in Virginia, please see the U.S. Geological Survey (USGS) Virginia Science Center’s Web site, http://va.water.usgs.gov/.

Precipitation

The following maps show southeastern U.S. precipitation amounts (top map) and the percent of normal precipitation for the given location at this time of year (bottom map) over the seven-day period ending August 18, 2015.  The maps were accessed on 8/19/15 from the National Oceanic and Atmospheric Administration’s (NOAA) Southeast Regional Climate Center, located at the University of North Carolina in Chapel Hill; online at http://www.sercc.com/climateinfo/precip_maps.  As of that date, these data were provisional (needing to be verified for accuracy and subject to possible revision).
Precip Aug18Precip perc Aug 18

Another source of precipitation data is the National Weather Service’s Advanced Hydrologic Prediction Service, http://water.weather.gov/precip/, provides maps showing precipitation nationwide or by state for specific days, months, or years. The site also has the capability to show county boundaries. Shown below are U.S. maps of precipitation and percent of normal precipitation for the 7-day precipitation ending at 8 a.m. Eastern Daylight Time on August 19, 2015. (Please note that UTC, the time shown on the map below, is five hours ahead of Eastern Standard Time and four hours ahead of Eastern Daylight Time.)

full.phpprecipperc us

Stream Flow

Average Virginia stream flow over the seven-day period ending August 18, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia, accessed online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap on 8/19/15.  The map’s color-coded dots compare the previous week’s average stream flows to the normal flow levels for that week over the historical record for each gaging station.  The “bluer” the color of the dots, the higher the percentile and flow relative to normal for the site and time of year; the “redder” the dots, the lower the percentile and flow relative to normal. The color codes/percentile classes used by USGS are as shown in the chart following the map.

streams Aug 18KEEP on deskto - Stream flow code graph

Mid-month Drought Status Update

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, produces a daily map rating drought-status indicators. Shown below is the August 19, 2015, map.  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, http://www.deq.virginia.gov/Programs/Water/WaterSupplyWaterQuantity/Drought.aspx.

Drought VA Aug 19

Virginia Precipitation and Stream Flow for the 7-day Period Ending August 11, 2015

Below are images showing precipitation in Virginia and other areas of the southeastern United States, and stream flow in Virginia, over the seven-day period ending August 11, 2015.  The Virginia Water Resources Research Center thanks the agencies mentioned below for providing precipitation and stream-flow information and images.

For monthly reviews of precipitation, stream flow, and drought, please see the News Grouper posts available at this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Monthly+Water+Status.

For more information on current and historical surface-water and groundwater conditions in Virginia, please see the U.S. Geological Survey (USGS) Virginia Science Center’s Web site, http://va.water.usgs.gov/.

Precipitation

The following maps show southeastern U.S. precipitation amounts (top map) and the percent of normal precipitation for the given location at this time of year (bottom map) over the seven-day period ending August 11, 2015.  The maps were accessed on August 12 from the National Oceanic and Atmospheric Administration’s (NOAA) Southeast Regional Climate Center, located at the University of North Carolina in Chapel Hill; online at http://www.sercc.com/climateinfo/precip_maps.  As of that date, these data were provisional (needing to be verified for accuracy and subject to possible revision).

Precip Aug11Precip perc Aug 11

Another source of precipitation data is the National Weather Service’s Advanced Hydrologic Prediction Service, http://water.weather.gov/precip/, provides maps showing precipitation nationwide or by state for specific days, months, or years.  The site also has the capability to show county boundaries.  Shown below are maps of precipitation and percent of normal precipitation for the 7-day precipitation ending at 8 a.m. Eastern Daylight Time on August 12, 2015.  (Please note that UTC, the time shown on the map below, is five hours ahead of Eastern Standard Time and four hours ahead of Eastern Daylight Time.)  Precip US Aug 12Precip perc US Aug 12

Stream Flow

Average Virginia stream flow over the seven-day period ending August 11, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia, accessed online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap on August 12.  For 141 stream-gaging stations in Virginia and just beyond the state border, the map’s color-coded dots compare the previous week’s average stream flows to the normal flow levels for that week over the historical record for each gaging station.  The “bluer” the color of the dots, the higher the percentile and flow relative to normal for the site and time of year; the “redder” the dots, the lower the percentile and flow relative to normal.  The color codes/percentile classes used by USGS are as shown in the chart following the map.

Streams Aug 11KEEP on deskto - Stream flow code graph

Virginia Water Status Report as of the End of July 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 July 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: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Precipitation Icon by George WillsHere are National Weather Service (NWS) preliminary (still needing verification) precipitation totals for July 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 July 2015

Precipitation

 

Normal for Month Aug. 2014-July 2015 Precipitation

 

Normal Annual Precipitation
Blacksburg 4.26 4.26 42.75 40.89
Bluefield (Merc. Co. airport, near Va.-W.Va. state line) 5.14 4.17 43.20 39.63
Bristol (Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va.-Tenn.) 5.79 4.69 40.45 41.01
Charlottesville (Char.-Albemarle Airport) 4.01 4.32 39.4 42.71
Danville 7.24 4.59 44.87 44.41
Lynchburg 3.79 4.36 38.28 41.57
Norfolk 7.93 5.14 52.16 46.53
Richmond 5.89 4.51 43.60 43.60
Roanoke 4.29 4.04 45.72 41.25
Wallops Island (Accomack County) 4.41 4.09 43.33 40.84
Washington-Dulles Airport (Loudoun County) 4.89 3.67 41.20 41.54

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 provisional (still needing verification) maps of the percent-of-normal precipitation for the previous 30 days, 60 days, and 90 days, through August 3, 2015.Precipperc30daysAug3

Precipperc60daysAug3Precipperc90daysAug3

Stream flow icon by George Wills
According to the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/classic.php?m=mv01d&r=va&w=real%2Cmap), monthly average stream flow values for July 2015 at 150 stream gages in Virginia and just beyond the state border were in the normal range at about 40% of gages, below normal at about 5%, above normal at about 34%, and much above normal at about 21%. 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 July 2015KEEP on deskto - Stream flow code graph


Drought Watch icon by George WillsDROUGHT IN VIRGINIA

The weekly National Drought Monitor map from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for July 28, 2015, showed Virginia as being drought-free, which has been the case since the Drought Monitor report for July 7, 2015. The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.”

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

For comparison, here are Virginia ratings from previous Drought Monitors from about one month, two months, three months, and one year ago:
6/30/15 – 13% abnormally dry;
5/26/15 – 32% abnormally dry;
4/28/15 – drought-free;
7/29/14 – 27%abnormally dry.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on July 16, 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 next report is scheduled for September 2015. 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.

Following is an excerpt from the beginning of the July 16, 2015, report, summarizing statewide conditions at that time: “The typical summer pattern of scattered thunderstorms produced normal to above normal rainfall across Virginia over the past month. As a result, stream discharge rates have been normal to above normal depending upon local rainfall amounts. Groundwater levels in some of the Climate Response Network observation wells have continued a normal summer decline, while others, particularly in the eastern half of Virginia, have rebounded. Maps of precipitation as a percent of normal rainfall illustrate that most of Virginia has received normal or above-normal rainfall during the past 30, 60 and 90 days. A large area in southern Virginia within the upper portions of the New River and Roanoke River basins has received less than normal rainfall for the current water year (since October 1, 2014). Note that precipitation estimates based on radar in parts of northwestern Virginia along the Virginia-West Virginia border and on the boundary between the Upper James and Shenandoah drought-evaluation regions are generally considered to be underestimated due to that area’s distance from radar stations.”

The Drought Monitoring Task Force also produces a daily map rating drought-status indicators. Shown below is the July 31, 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 Jul31

MORE ON GROUNDWATER LEVELS

More 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 ELSEWHERE

The July 28, 2015, Drought Monitor rated 44.2% of the United States (including all or parts of 38 states, plus Puerto Rico) as being abnormally dry or worse, and it rated 14.4% of the country (including all or parts of 15 states, plus Puerto Rico), as being in severe drought or worse (categories D2, D3, and D4). The abnormally dry or worse percentage increased sharply from just a week earlier—39.4% on 7/21/15—largely because during Alaska’s abnormally dry percentage increased from 57% to 71%.

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:
6/30/15 – 41.7% abnormally dry or worse; 13.0% severe drought or worse;
5/26/15 – 46.4% abnormally dry or worse; 11.9% severe drought or worse;
4/28/15 – 48.5% abnormally dry or worse; 16.7% severe drought or worse;
7/29/14 – 39.8% abnormally dry or worse; 19.0% severe drought or worse.

In the following states, over 50% of the state was categorized by the July 28 report as being in severe-or-worse drought.
California – 95% (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.
Idaho – 52% (with 22% in extreme drought).
Nevada – 76% (with 40% in extreme or exceptional drought).
Oregon – 100% (with 48% in extreme drought).
Washington – almost 100% (with 32% 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.html. Shown below is the outlook map available on August 5, 2015.

Seasonal Drought Outlook