Since the beginning of 2012, the contiguous United States has been experiencing drier than average conditions. This lack of precipitation is affecting water availability for agriculture and municipal use, as well as increasing concerns about soil quality and wildfires.
The map above shows the percent of average precipitation across the United States from January – April. Shades of brown indicate areas that received less than 100 percent of average precipitation while green indicates up to 200 percent of average.
While patches of brown cover both sides of the country, some areas did receive more rain than usual. Wetter than average conditions occurred across the central regions of the country and the Pacific Northwest. In the Pacific Northwest, above average precipitation contributed to higher than normal mountain snowpack at the end of the snow season. The amount of snowpack in the springtime is important in determining water supply for the region for the upcoming summer period.
Elsewhere, water managers might be more concerned. Both the eastern third of the nation and much of the interior West have been drier than average for the past four months. Maryland and Delaware experienced record-breaking dry conditions, and an additional six states had precipitation totals ranking among the ten driest.
According to the U.S. Drought Monitor, as of May 1st, 38.2 percent of the contiguous United States was experiencing drought conditions, an increase from the 31.9 percent at the beginning of 2012. The color-coded, drought classification map above shows abnormally dry areas, as well as moderate to exceptional drought conditions. Drought worsened across the Northeast, Southeast, and the Interior West while beneficial precipitation significantly improved drought conditions across the Southern Plains and western Gulf of Mexico.
These climate statistics and many others are part of NOAA’s National Climate Summary. NOAA’s National Climatic Data Center (NCDC) produces these monthly climate reports for the United States describing the precipitation conditions as well as temperatures and severe events. NCDC also produces a global analysis of monthly climate, which summarizes global temperatures and precipitation, and places each month’s conditions into a historical perspective.
NOAA maps by climate.gov team, based on climate division data from the NCDC and drought data released on May 3 by the U.S. Drought Monitor. Caption by Susan Osborne and Caitlyn Kennedy. Science reviewer: Jake Crouch, National Climatic Data Center.