Category Archives: Water Supply

Southeastern U.S. Precipitation and Virginia Stream Flow Look-back at Winter 2014-15

On March 26, 2015, with Virginia’s and the Northern Hemisphere’s spring equinox just a few days gone by, here’s a look back at what happened with rainfall in the southeastern United States and stream flow in Virginia in winter 2014-25.  The Virginia Water Resources Research Center thanks the agencies mentioned above for their work to providing these valuable assessment products.

Precipitation

The following maps, from the National Oceanic and Atmospheric Administration’s (NOAA) Southeast Regional Climate Center (SRCC), located at the University of North Carolina in Chapel Hill (http://www.sercc.com/climateinfo/precip_maps, accessed 3/26/15), show southeastern U.S. precipitation between December 26, 2014, and March 25, 2015 (first map), and how this rainfall compared to historical normal values for that period (second map). These data are provisional. (For perspective, Virginia’s statewide average annual rainfall since 1895 has been about 43 inches, according to the SRCC’s “Monthly and Seasonal Climate Information” Web page at http://www.sercc.com/climateinfo/monthly_seasonal.)

precip 90 dayprecip perc 90 day

In the second map, note the brown and red areas—indicating precipitation at least 10 percent below normal for the period—in a swath of Virginia from the southwest to the center of the state. These levels have helped cause the occurrence of “abnormally dry” conditions in about 20 percent of Virginia as of March 24, 2015, according to the report of the U.S. Drought Monitor for that date. (The Drought Monitor is produced by the University of Nebraska-Lincoln and is available online at http://droughtmonitor.unl.edu/.) Virginia has had some areas rated as abnormally dry since the April 22, 2014, Drought Monitor report.

Outside of Virginia, note the large swath of below-normal precipitation from Virginia south to the Gulf Coast. The March 24, 2015, Drought Monitor rated about 25 percent of the southeastern United States as abnormally dry.

For another color-coded map of precipitation in Virginia or any other state of your choosing, see the National Weather Service’s Advanced Hydrologic Prediction Service’s nationwide map of precipitation, with daily, monthly, and yearly archives; online at http://water.weather.gov/precip/.

Stream Flow

The first graph below, from the U.S. Geological Survey’s (USGS) “WaterWatch—Current Water Resources Conditions” Web site (http://waterwatch.usgs.gov/new/index.php?id=pa01d&sid=w__plot&r=va), accessed 3/26/15), compares average daily stream flow to historical records for the 45-day period of Feb.7—Mar. 25, 2014. The second graph covers the period since January 2001. The data in the graphs come from 88 sites that have at least 30 years of records. Each graph uses a “stream flow index,” which measures how a site’s average stream flow over 24 hours compares to the historical average stream flow for that same site and date. The graphs shows a further average: the stream flow index averaged statewide over the 88 sites.

Streams 45 daysStreams 10 years

 

Other Water Status Posts on the Water Central News Grouper

Previous seasonal look-backs are at this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Seasonal+Look-back.

Monthly water-status updates are at this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Virginia+Water+Status.

Virginia Precipitation and Stream Flow for the 7-day Period Ending March 24, 2015

This post presents images showing precipitation in Virginia and other areas of the southeastern United States, and stream flow in Virginia, over the seven-day period ending March 24, 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 March 24, 2015.  The maps were accessed on March 25 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 Mar 24Precip perc Mar 24

 

For another precipitation-information source: 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 is the map of seven-day precipitation ending at 8 a.m. Eastern Daylight Time on March 25, 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 Mar 25

Stream Flow

Average Virginia stream flow over week ending March 24, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap, accessed 3/25/15).  The map compares the previous week’s average stream flows at 139 stream-gaging stations in Virginia and just beyond the state border to the normal flow levels for that week over the historical record for each gaging station.  The color codes/percentile classes used by USGS to compare flows to historical records are as shown in the following chart (the higher the percentile and the “bluer” the color, the higher the flow relative to normal for the site and time of year).

KEEP on deskto - Stream flow code graphStreams Mar 24

On Virginia Water Radio for 3-23-15: Good-bye Winter, and Thanks for the Water

This week, Virginia Water Radio features music to mark the passing of winter into spring, and to recognize the importance of the water winter leaves behind.  Click here to have a listen (3 min./42 sec.)

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 Precipitation and Stream Flow for the 7-day Period Ending March 17, 2015, Plus a Mid-Month Drought Assessment

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 March 17, 2015.  Also below is a map showing the status of drought indicators in Virginia as of March 17, 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 March 17, 2015.  The maps were accessed on March 18 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 Mar 17Precip Perc Mar 17 

For another precipitation-information source: 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 is the map of seven-day precipitation ending at 8 a.m. Eastern Daylight Time on March 18, 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 Mar 17

 

Stream Flow

Average Virginia stream flow over week ending March 17, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap, accessed 3/18/15).  The map compares the previous week’s average stream flows at 139 stream-gaging stations in Virginia and just beyond the state border to the normal flow levels for that week over the historical record for each gaging station.  The color codes/percentile classes used by USGS to compare flows to historical records are as shown in the following chart (the higher the percentile and the “bluer” the color, the higher the flow relative to normal for the site and time of year).

Stream code graphStreams Mar 17

 

Drought Update

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on March 17, 2015.  The report typically includes 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.  Task Force reports and other current drought-status information are available online at http://www.deq.virginia.gov/Programs/Water/WaterSupplyWaterQuantity/Drought.aspx.

Following is an excerpt from the beginning of the March 17, 2015, report, summarizing statewide conditions: “The dry conditions that had persisted during the previous months in parts of the Commonwealth were relieved by widespread rainfall and snowfall events during late February and early March. Consequently, stream discharge and groundwater levels returned to normal or near-normal levels at nearly all monitoring stations…. Maps of precipitation as a percent of normal rainfall illustrate that most of the Commonwealth received near normal to above-normal precipitation during the past 60 days…. Areas that have received less than 80% of normal precipitation since the beginning of the current water year on October 1, 2014, include parts of [the] Roanoke Basin and relatively small areas in southeastern Virginia, the New River [basin], and the Middle and Upper James drought-evaluation regions.”

The Drought Monitoring Task Force also produces a daily map rating groundwater levels (GW), precipitation deficits (Prcp), reservoir storage (Res), and stream flow (Flow) conditions across the Commonwealth. In each area, a color code indicates “normal,” “watch,” “warning,” or “emergency conditions.” Shown below is the March 17, 2015, map.  Any given day’s current map and more information on the ratings are available the Task Force Web site listed above.
Drought Va Mar 17

Virginia Precipitation and Stream Flow for the 7-day Period Ending March 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 March 11, 2015.  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 past seven days.   The maps were accessed on 3/12/15 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 3/12/15, these data are provisional (needing to be verified for accuracy and subject to possible revision).

Precip Mar11Precip perc Mar 12

For another precipitation-information source: 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.  As an example, shown below is the map of one-day precipitation ending at 8 a.m. Eastern Daylight Time on March 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 Mar12

Stream Flow

Average Virginia stream flow over week ending March 11, 2015, is indicated in the map below, from the U.S. Geological Survey WaterWatch for Virginia (online at http://waterwatch.usgs.gov/classic.php?m=pa07d&r=va&w=mv01d%2Cmap, accessed 3/12/15).  The map compares the previous week’s average stream flows at 140 stream-gaging stations in Virginia and just beyond the state border to the normal flow levels for that week over the historical record for each gaging station.  The color codes/percentile classes used by USGS to compare flows to historical records are as shown in the following chart (the higher the percentile and the “bluer” the color, the higher the flow relative to normal for the site and time of year).

Stream code graph

Streams

 

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

Here is the Virginia Water Central News Grouper’s monthly water-status report, as of the end of February 2015. The Virginia Water Resources Research Center thanks the agencies mentioned below for providing the data and maps used in this post.

PRECIPITATION

Here are National Weather Service (NWS) preliminary precipitation totals for February 2015 at 11 Virginia or near-Virginia locations, with the amount above (+) or below (-) normal for this month of the year historically. All values are in inches, rounded to the nearest 0.1 inch from NWS values.

Location Observed Precipitation(inches) Above (+) or Below (-) Normal (inches)
Blacksburg 2.1 -0.7
Bluefield (Va.-W.Va. state line) 2.1 -0.7
Bristol (Tri-Cities Airport in Tenn., about 20 miles from Bristol, Va.-Tenn.) 3.1 -0.4
Charlottesville 1.0 -1.7
Danville 2.3 -0.7
Dulles Airport (Loudoun County) 1.8 -1.0
Lynchburg 2.5 -0.4
Norfolk 2.5 -0.6
Richmond 3.8 +1.0
Roanoke 2.6 -0.3
Wallops Island (Accomack County) 3.1 +0.3

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 February 28, 2015. Please note that the scale is different for the 90-day map.

Precip perc 30 days Feb 28Precip perc 60 days Feb 28Precip perc 90 days Feb 28


STREAM FLOW

According to the U.S. Geological Survey WaterWatch for Virginia, average stream flow values for February 2015 at 123 stream gages in Virginia and just beyond the state border were in the normal range at about 32 percent of gages and below normal at about 68 percent.   (Please note: The USGS map for the average monthly flow in Virginia usually has readings from about 140 to 150 stations, but (according to the USGS) some stations during this period were affected by ice, so a monthly average could not be calculated. The empty circles on the map below indicate those stations.)  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 as follows:
Stream code graphStreams Feb 2015

 

 


DROUGHT

The weekly National Drought Monitor map from the University of Nebraska-Lincoln (http://droughtmonitor.unl.edu/) for March 3, 2015, categorized about 31 percent of Virginia as being abnormally dry. That area included the upper James River basin, the upper Roanoke River basin, essentially all of the New River basin, and the upper Clinch/Holston basin).

The Drought Monitor notes that it “focuses on broad-scale conditions [and] local conditions may vary.” The 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:
1/27/15 – 10 percent abnormally dry;
12/30/14 – 16 percent abnormally dry;
11/25/14 – 38 percent abnormally dry;
3/4/14 – drought-free.

The Virginia Drought Monitoring Task Force, a collaboration of state and federal agencies, issued its most recent Drought Status Report on February 24, 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 groundwater levels (GW), precipitation deficits (Prcp), reservoir storage (Res), and stream flow (Flow) conditions across the Commonwealth. In each area, a color code indicates “normal,” “watch,” “warning,” or “emergency conditions.” The March 1, 2015, map is shown below. The current map and more information on the ratings are available the Task Force Web site listed above.

Drought in VA Mar 1 2015

Looking at drought conditions beyond Virginia: The March 3, 2015, U.S. Drought Monitor rated 49.4 percent of the United States (including all or parts of 41 states) as being abnormally dry or worse, and it rated 13.1 percent of the country (including all or parts of 12 states), as being in severe drought or worse (categories D2, D3, and D4). (On August 7, 2012, 38.5 percent of the country was in the three worst categories; that was the highest percentage in these categories reported by the Drought Monitor since it began in 2000.)

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:
1/27/15 – 43.4 percent abnormally dry or worse; 14.1 percent severe drought or worse;
12/30/14 – 39.2 percent abnormally dry or worse; 14.1 percent severe drought or worse;
11/25/14 – 39.5 percent abnormally dry or worse; 14.0 percent severe drought or worse;
3/4/14 – 46.8 percent abnormally dry or worse; 18.0 percent severe drought or worse;

In the following states, over 50 percent of the state was categorized by the March 3 report as being in severe-or-worse drought:
California – 93% (with 67% in extreme or exceptional drought; California has had over 90 percent of its area categorized in severe-or-worse drought every week since February 11, 2014, and the Golden State had 100 percent in those categories from May 13—July 29, 2014);
Nevada – 64% (with 48% in extreme or exceptional drought).

Here’s a comment from the March 3 Drought Monitor on the kind of winter some New Englanders have experienced in 2014-15: “As of March 1 [2015], the National Weather Service Forecast Office in Boston reported that several locations experienced their snowiest winter on record including Boston (99.4”) and Worcester, MA (101.4”)….”

For a look ahead, the National Weather Service/Climate Prediction Center’s “U.S. Seasonal Drought Outlook” for the next 90 days is available at http://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_summary.html. Shown below is the outlook map available on March 3, 2015.

Drought outlook

 

PREVIOUS MONTHLY WATER-STATUS REPORTS

Please see this link: https://vawatercentralnewsgrouper.wordpress.com/?s=Water+Status.

Water Conservation at Commercial Car Washes is Focus of Certification Program by International Carwash Association

Following a snowy February 2015, many Virginians may be thinking it’s time to wash the dirt and road salt off of their vehicles.

The WaterSavers® Program of the International Carwash Association promotes reduced use of fresh water, proper handling of the used water, backflow prevention, and cleaning quality at commercial car-wash facilities.  The program Web site, at http://www.carwash.org/watersavers, provides information for businesses to seek certification in the program, and a location tool for consumers to find certified facilities.  More information about the International Carwash Association is available at their main Web site, http://www.carwash.org/, or contact the group at in Chicago at (888) 422-8422; e-mail: info@carwash.org.

U.S. EPA information on water use and management in vehicle washing is available in the EPA’s “WaterSense” program document online (as PDF) at http://www.epa.gov/watersense/commercial/docs/watersense_at_work/#/179/zoomed.