Category Archives: Weather

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

 

On Virginia Water Radio for 3-9-15: Tornado Preparedness

This week, Virginia Water Radio focuses tornado preparedness and Virginia’s annual statewide tornado drill, held annually in March.  Click here to have a listen (3 min./38 sec.)

Pulaski tornado house

Heavily damaged house in Pulaski, Virginia, on April 14, 2011, following an April 8 tornado in the area.

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 Statewide Tornado Drill Will Be March 17, 2015

Virginia’s annual statewide tornado drill will be held March 17, 2015, at 9:45 a.m.

Below is the March 2, 2015, news release from the Virginia Department of Emergency Management on this year’s drill.  The news release is located at this link: http://www.vaemergency.gov/news/news-releases/2015/tornadoDrillSignUp.

More information from the VDEM on tornado safety is available online at http://www.vaemergency.gov/readyvirginia/stayinformed/tornadoes.  Please see also the Water Central News Grouper Post, Tornado Preparedness in Virginia.

Draper Apr11 08 USED Grouper 3-6-15

Building debris and snapped trees (background) in Draper, Va. (Pulaski County) from a tornado in early April 2008.

 

NEWS RELEASE STARTS HERE
For more information:
Dawn Eischen, VDEM
(804) 897-9730 or 674-2400
dawn.eischen@vdem.virginia.gov

RICHMOND, Va. – Although winter is still upon us, tornadoes can happen any time of year, making preparedness for these potentially deadly storms even more important. To be better prepared, businesses and organizations, schools and colleges, and families and individuals can practice taking cover from tornadoes by participating in the annual Statewide Tornado Drill Tuesday, March 17, at 9:45 a.m. So far, more than 392,500 people have registered for the drill.

Registration for the tornado drill is not necessary, but people can learn more and show their support by signing up at www.ReadyVirginia.gov.

“Tragically, many Virginia families and communities have been affected by deadly tornadoes in recent years,” said Dr. Jeff Stern, state coordinator of emergency management. “Twelve tornadoes impacted the state in 2014, causing numerous injuries and more than $700,000 in property damage. Knowing what to do when a tornado warning is issued can save your life, so we encourage everyone to participate in the upcoming Statewide Tornado Drill.”

The annual drill is a joint effort of the Virginia Department of Emergency Management and the National Weather Service.

“Receiving a tornado warning as quickly as possible can make the difference between life and death,” said Bill Sammler, NWS warning coordination meteorologist. “One of the fastest ways for people to get a tornado warning is by NOAA Weather Radio, which provides warning information directly from the nearest National Weather Service office. However, cell phone apps such as Ready Virginia are also available that quickly provide critical warning information at little or no cost. Wireless Emergency Alerts (WEA) also provide tornado and flash flood warnings via text message to any compatible cell within the warning area, even if you are visiting or just traveling through an affected area.”

To start the tornado drill, at 9:45 a.m. March 17 the NWS will send a test tornado warning that will trigger a tone alert and broadcast message on NOAA Weather Radio. The message will be picked up by TV and radio broadcasts, simulating what listeners will hear during an actual tornado warning. When the test tornado warning is sounded, respond as you would during an actual tornado warning:

  • Go immediately to a safe place – usually the lowest level of your home, office or school – and stay there until the warning expires.
  • If there is no basement, go to a windowless interior room such as a closet, bathroom or interior hallway.
  • Crouch as low as possible to the floor, facing down and covering your head with your hands.
  • In case of widespread inclement weather March 17, the Statewide Tornado Drill will be held March 24.

NOAA Weather Radios target warnings to single or multiple localities, using city/county specific codes. They are available at electronics and sporting goods stores, discount and department stores, and online. They come in battery-powered models, and many also have AM/FM bands, which can be valuable during power outages. In addition, special-needs NOAA Weather Radios can warn deaf and hard-of-hearing persons of hazardous conditions, giving them around-the-clock, up-to-the-minute weather information, and potentially life-saving warnings.

For help in conducting a tornado drill and to register for the statewide drill, go to www.ReadyVirginia.gov.