Drought expanded and intensified in Texas and Florida but decreased elsewhere, leading to a net decrease in area but a slight increase in intensity of drought across the country, according to the March 5 U.S. Drought Monitor map.
Incremental changes based on weeks of wet and dry patterns led to a net decrease in the total area of the United States in moderate drought or worse, to 44.93 percent compared with 45.63 percent the week before, but a net increase in severe and extreme drought, according to statistics released with the map. This is down from last year’s peak on Sept. 25, 2012, when the map showed 54.77 percent of the entire country in moderate drought or worse, including Alaska, Hawaii and Puerto Rico.
This week’s U.S. Drought Monitor author, Matthew Rosencrans, noted in narrative accompanying the map that since Nov. 1, Daytona Beach, Florida, has received 4.64 inches of rain, only 40 percent of the normal 10.5 inches, which makes it the 7th driest period for that area in 80 years. Similarly, Ocala, Florida, has received 5.4 inches of rain, also 40 percent of the 11.5 inches that are normal, making it the 11th driest period in 120 years.
In West Texas, water stored in reservoirs is at record lows, and low humidity and high winds contributed to the expansion of drought in southern Texas, said Rosencrans, who is with the National Oceanic and Atmospheric Administration’s Climate Prediction Center.
Rains led to improvements in drought in southern Georgia and in the Oklahoma Panhandle, while snow eased drought in Colorado. Precipitation from a winter storm moving through the Northwest also eased drought in southern Idaho and northern Utah, he noted.
U.S. Drought Monitor authors synthesize many drought indicators into a single map that identifies areas of the country that are abnormally dry (D0), in moderate drought (D1), in severe drought (D2), extreme drought (D3) and exceptional drought (D4).
The U.S. Drought Monitor map is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the National Oceanic and Atmospheric Administration, the U.S. Department of Agriculture, and about 350 drought observers across the country. It is released each Thursday based on data through the previous Tuesday morning.
Statistics for the percent area in each category of drought are automatically added to the U.S. Drought Monitor website each week for the entire country and Puerto Rico, for the 48 contiguous states, for each climate region, and for individual states. U.S. Drought Monitor data online goes back to January 2000.
http://drought.unl.edu/MonitoringTools/USDroughtMonitor/DroughtMonitorTips.aspx
U.S. Drought Monitor map, statistics and narrative summary: http://droughtmonitor.unl.edu
National Climatic Data Center’s State of the Climate Drought Summary:
http://www.ncdc.noaa.gov/sotc/drought/
Seasonal Drought Outlook:
http://www.cpc.ncep.noaa.gov/products/expert_assessment/seasonal_drought.html