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

On December 24, 2014, with Virginia’s and the Northern Hemisphere’s shortest day of 2014 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 fall 2014.  The Virginia Water Resources Research Center is grateful to the agencies mentioned above for their work to providing these valuable assessment products.

Precipitation

The following “Percent of Normal Precipitation” graph, from the National Oceanic and Atmospheric Administration’s (NOAA) Southeast Regional Climate Center, located at the University of North Carolina in Chapel Hill (http://www.sercc.com/climateinfo/precip_maps, accessed 12/24/14), shows how precipitation values across the southeastern United States between September 25 and December 23, 2014, compared to historical normal values for that periodThese data are provisional.  Note the yellow and brown areas in Virginia, indicating below-normal rainfall for the period. These rainfall levels have helped lead to the occurrence of “abnormally dry” conditions in about 33 percent of Virginia, according to the December 23, 2014, report of the U.S. Drought Monitor. (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.

Precip three months Dec 2014

 

Outside of Virginia, note that much of the southeastern United States received below-normal precipitation during this period, while above-normal precipitation fell in much of Florida and southern Georgia, along the Appalachians, and in parts of North Carolina and South Carolina.   The December 23, 2014, Drought Monitor rated about 40 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 12/24/14), compares average daily stream flow to historical records for the period Nov. 7—Dec. 22, 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.

Stream flow 45

 

Streamflow longterm

 


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.

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