The Drought Monitoring Task Force is an interagency group of technical representatives from state and federal agencies responsible for monitoring natural resource conditions and the effects of drought on various segments of society. The Task Force meets to assess conditions and make recommendations regarding drought status. The Task Force periodically releases Drought Status Reports summarizing drought conditions in the Commonwealth.
Latest Drought Status Report
Partners
The Drought Monitor provides a weekly overview of where in the United States drought is emerging, lingering, subsiding or forecast. The Monitor is produced jointly by the National Weather Service's Climate Prediction Center, the U.S. Department of Agriculture, and the National Drought Mitigation Center at the University of Nebraska-Lincoln.
The three-way partnership is responding to the need for accurate, centralized drought information by developing a map that summarizes information from numerous drought indices and indicators on a single, easy-to-read color map.
The USGS maintains a network of wells to monitor the effects of droughts and other climate variability on ground-water levels. The network consists of a national network of about 140 wells monitored as part of the Ground-Water Resources Program, supplemented by wells in some States monitored as part of the Cooperative Water Program.
Virginia currently has 20 wells monitored in real-time as part of the Virginia Climate Response Network through a partnership between the USGS and Virginia DEQ.
The data used to produce this map are provisional and have not been reviewed or edited. They may be subject to significant change.
The map depicts streamflow conditions as computed at USGS gaging stations. The colors represent real-time streamflow compared to percentiles of historical daily streamflow for the day of the year. This map represents conditions relative to those that have historically occurred at this time of year.
The "Real-time streamflow" map tracks short-term changes (over several hours) in rivers and streams. Although the general appearance of the map changes very little from one hour to the next, individual sites may change rapidly in response to major rain events or to reservoir releases.
The data used to produce this map are provisional and have not been reviewed or edited. They may be subject to significant change.
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Explanation - Percentile class
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Low
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< 10
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10 - 24
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25 - 75
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76 - 90
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> 90
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High
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Not ranked
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University of Virginia Climatology Office
Precipitation Deficits:
The Virginia State Climatology Office produces precipitation deficits by comparing current precipitation amounts with historical precipitation values as a percent of normal long-term average values. Comparisons are made for each drought evaluation region. Normal long-term average precipitation is defined as the mean precipitation for a thirty-year period of record for the area and time period being evaluated.
Precipitation amounts are evaluated based on the water year (beginning October 1). Water years are natural dividing points for water supply drought as precipitation that falls in the first six months of a water year is analogous to putting money in the bank. Precipitation that occurs during this six month period has the potential to recharge ground water, which will sustain stream flows and support withdrawals from wells during the following six month period when moisture deficits naturally develop as evaporation and plant transpiration generally exceed precipitation.
National Weather Service
The National Weather Service (NWS) of the National Oceanic and Atmospheric Administration (NOAA) produces a series of webpages as part of its Advanced Hydrologic Prediction Service (AHPS). These webpages provide information on observed precipitation, river flows and air quality, as well as precipitation and stream flow forecasts. The NWS radar-generated precipitation data are used by DEQ to represent current observations in the determination of precipitation deficits as drought indicators. Current and recent precipitation data for the Commonwealth of Virginia can be examined on the NWS Virginia AHPS page.