According to the September 15, 2020, U.S. Drought Monitor, moderate to exceptional drought covers 32.8% of the United States including Puerto Rico, a slight increase from last week’s 32.7%. The worst drought categories (extreme to exceptional drought) decreased slightly from 9.8% last week to 9.6% this week.
A strong upper-level low moved from the southwestern contiguous United States to the Great Lakes early in the week. Its departure allowed a subtropical high-pressure ridge to reassert itself over the southern two-thirds of the contiguous United States by the end of the week. Surface lows and a cold front associated with the upper-level low generated above-normal precipitation across, and brought much colder-than-normal temperatures to, the Southwest, southern to central Plains, and Mid-Mississippi Valley to western Great Lakes.
A lobe of the upper-level ridge maintained its strength over the western contiguous United States throughout the week, keeping the weather dry and helping to maintain widespread wildfires. Another lobe of the subtropical ridge kept the Southeast to Northeast warmer and mostly drier than normal.
Hurricane Sally developed and slowly meandered across the eastern Gulf of Mexico as the week progressed, spreading rain across Florida and nearing the central Gulf coast as the week ended. Drought and abnormal dryness expanded or intensified in the West, northern Plains, Northeast, and parts of the Ohio Valley. The precipitation in the southern and central Plains to western Great Lakes brought relief and contracted drought in those areas. Contraction almost balanced expansion, with the overall U.S. drought footprint growing slightly this week.
Abnormal dryness and drought are currently affecting over 109 million people across the United States including Puerto Rico—about 35.1% of the 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. See their recent news releases.
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.