According to the December 24, 2024 U.S. Drought Monitor (USDM), moderate to exceptional drought covers 33.2% of the United States including Puerto Rico, a decrease from last week’s 32.5%. The worst drought categories (extreme to exceptional drought) slightly increased from 3.8% last week to 3.9%.
The upper-level circulation pattern over the contiguous U.S. (CONUS) during this USDM week (December 18–24) was mostly zonal with several weather disturbances moving through the west-to-east flow. The weather disturbances consisted of a series of upper-level short-wave troughs, with upper-level ridges in between them. The troughs dragged fronts and surface low-pressure systems along with them. The troughs and their fronts spread Pacific moisture across parts of the West and tapped Gulf-of-Mexico moisture as they moved east of the Rockies.
The week ended up wetter than normal from northern California to the Pacific Northwest, from southeastern Oklahoma to the Ohio Valley, and across parts of the northern Plains, Great Lakes, Northeast, and central Appalachians. The rest of the CONUS was drier than normal. The fronts funneled cold Canadian air across areas east of the Rockies. But the upper-level ridges drew warmer air from the South across much of the CONUS, so much of the country from the West Coast to the Great Plains ended up warmer than normal for the week, with the northern Plains to Northeast cooler than normal.
Alaska and Hawaii were mostly warmer and drier than normal, while Puerto Rico and the U.S. Virgin Islands had a mostly warmer- and wetter-than-normal week.
Drought and abnormal dryness contracted in the wet areas from northern Tennessee to the eastern Great Lakes and southern New England. But drought or abnormal dryness expanded or increased in intensity in parts of the West, southern Plains, and Southeast.
Nationally, expansion was more than contraction, so the nationwide moderate to exceptional drought area percentage increased this week. Abnormal dryness and drought are currently affecting over 231 million people across the United States including Puerto Rico—about 74.2% of the population.
The full U.S. Drought Monitor weekly update is available from Drought.gov.
In addition to Drought.gov, you can find further information on the current drought 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. The U.S. Department of Agriculture’s World Agriculture Outlook Board also provides information about the drought’s influence on crops and livestock.
For additional drought information, follow #DroughtMonitor on Facebook and X.
