According to the November 19, 2024 U.S. Drought Monitor (USDM), moderate to exceptional drought covers 38.0% of the United States including Puerto Rico, a decrease from last week’s 41.7%. The worst drought categories (extreme to exceptional drought) slightly increased from 4.1% last week to 4.2%.
The upper-level circulation pattern over the contiguous U.S. (CONUS) during this USDM week (November 13–19) consisted of a broad trough of low pressure over the West with a ridge of high pressure over the East. This pattern promoted a warm southerly flow over the central CONUS which, combined with the eastern ridge, gave most of the CONUS east of the Rockies a warmer-than-normal week. Superimposed over this broad circulation pattern was a series of Pacific weather systems that propagated eastward with the jet-stream flow. These systems combined with the western trough to give much of the West a cooler-than-normal week, especially from California to the Great Basin. These weather systems brought areas of rain and snow to parts of the West, with above-normal weekly precipitation over the Pacific Northwest to eastern Montana. Cold fronts and surface low-pressure systems associated with the weather systems tapped Gulf of Mexico moisture east of the Rockies to generate bands of above-normal precipitation: one band from New Mexico and western Texas to the western Great Lakes, and another band from the Lower Mississippi Valley to the Ohio Valley and Mid-Atlantic coast. Other parts of the country remained drier than normal this week, including California and Arizona to the western Dakotas, Deep South Texas, Florida and adjacent areas to the north, and most of the Northeast.
The week was mostly drier and cooler than normal in Alaska, warmer and drier than normal in Hawaii, and wetter than normal across the U.S. Virgin Islands with a mixed precipitation anomaly pattern over Puerto Rico.
Drought and abnormal dryness contracted or reduced in intensity in the Pacific Northwest, southern Great Plains to Upper Mississippi Valley, Lower Mississippi Valley to Ohio Valley, and central Appalachians to parts of the Mid-Atlantic Coast. Drought or abnormal dryness expanded or increased in intensity in some of the dry areas, including parts of Montana, Deep South Texas, the Southeast, and more of the Northeast.
Nationally, contraction was more than expansion, so the nationwide moderate to exceptional drought area percentage decreased this week, although the area experiencing extreme to exceptional drought increased slightly. Abnormal dryness and drought are currently affecting over 228 million people across the United States including Puerto Rico—about 73.3% 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 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.
For additional drought information, follow #DroughtMonitor on Facebook and Twitter.
