U.S. Drought: Weekly Report for May 16, 2023

According to the May 16, 2023 U.S. Drought Monitor, moderate to exceptional drought covers 17.0% of the United States including Puerto Rico, a decrease from last week’s 19.7%. The worst drought categories (extreme to exceptional drought) decreased from 4.9% last week to 3.6%.

A strong high-pressure ridge dominated the upper-level circulation over North America during this U.S. Drought Monitor week (May 10-16). Pacific weather systems attempted to move through the ridge across the contiguous U.S. They were slowed down by the ridge as they crossed the middle third of the contiguous U.S. The fronts and surface lows were associated with the weather system and tapped Gulf of Mexico moisture to spread above-normal precipitation across much of the Plains and Southeast. Parts of the Plains and Upper Mississippi Valley received heavy rain from the weather systems. Meanwhile, the ridge inhibited precipitation across much of the West, Great Lakes to Northeast, and Ohio Valley to Mid-Atlantic coast, where the week was drier than normal. 

Weekly temperatures averaged warmer than normal for much of the contiguous U.S., except for the Rio Grande Valley to the Great Basin and parts of the Northeast, where they were near to below average. The warmest temperature anomalies occurred in the Pacific Northwest and across the Mississippi Valley. 

Drought or abnormal dryness expanded or intensified in a few areas in Maine and the coastal Southeast. Conversely, drought or abnormal dryness contracted or reduced in intensity across much of the Plains to Mid-Mississippi Valley and parts of the Pacific Northwest and Mid-Atlantic region. 

Nationally, contraction exceeded expansion, with the nationwide moderate to exceptional drought area decreasing this week. Abnormal dryness and drought are currently affecting over 78 million people across the United States including Puerto Rico—about 25.2% of the population.