According to the May 22, 2018, U.S. Drought Monitor, moderate to exceptional drought covers 26.7% of the contiguous United States, a decrease from last week’s 28.3%. Extreme and exceptional drought—the worst categories—also contracted slightly to cover 9.4% of the Lower 48, down from 9.5% last week.
Like the previous two weeks, a broad-scale ridge in the upper atmosphere continued to dominate the weather over the contiguous United States during this U.S. Drought Monitor week, bringing another week of above-normal temperatures to much of the country. Upper-level weather systems slogged through the ridge, dragging fronts along with them which generally stalled out across the middle of the Lower 48, while the main storm track mostly stayed to the north in Canada.
A large and moist weather system, which originated over the Gulf of Mexico, slowly moved across the Southeast then up the East Coast, dumping several inches of rain across the eastern drought and abnormally dry areas. Two Pacific weather systems slowly moved across the country, leaving behind above-normal precipitation in parts of the West, Great Plains, and Midwest.
These weather systems missed other parts of the country, with the week ending up drier than normal across much of the coastal West, Southwest, Lower Mississippi Valley, Upper Mississippi Valley, and parts of northern New England. As a result, drought and abnormal dryness contracted in the Southeast, Mid-Atlantic, and parts of the Plains, while it expanded or intensified in parts of the West, Mississippi Valley, and other parts of the Plains.
Abnormal dryness and drought are currently affecting nearly 83 million people across the United States—about 26.6% of the country’s population.
In addition to Drought.gov, you can find further information on the current drought as well as on this week’s Drought Monitor update at the National Drought Mitigation Center.
The most recent U.S. Drought Outlook is available from NOAA’s Climate Prediction Center and the U.S. Department of Agriculture provides information about the drought’s influence on crops and livestock.