Latest Seasonal Assessment -
Moderate La Niña conditions continue over the equatorial Pacific. A slow decline in intensity is likely to result in ENSO-neutral conditions later this year, but for the forecast period through May 2021, it will continue to influence conditions across the Nation. As a result, the Climate Prediction Center's (CPC) seasonal forecast for March-May 2021 largely reflects the climate anomalies favored during La Niña, based on a composite of historical events.
During the past month, drought conditions as depicted in the Drought Monitor have changed in many parts of the Nation, but only a few scattered areas saw dramatic improvement or deterioration. In particular, there were no widespread changes to the intense, protracted drought across the Four Corners states and some adjacent parts of the High Plains and Great Basin. The one relatively small part of this region that experienced heavy precipitation and marked drought relief was noted in parts of Arizona. A series of storms brought a dramatic increase in higher-elevation snowpack. Across the state, only 10 to locally 50 percent of normal snowpack was reported in mid-January, which increased to between 50 and 100 percent of normal in mid-February. Some of the higher elevations improved from D4 to D2, and less dramatic improvement to D3 occurred in a swath across the central part of the state. Southwest Arizona, where drought has been less intense, also saw improvement. Farther west, a stormy pattern along the West Coast resulted in large areas of improvement from California to northward through Washington, with the most substantial changes in central Washington and the coastal areas of southwest Oregon and adjacent California. Other regions with notable improvements included the central Great Plains, the middle Mississippi Valley, and central Texas. In contrast, drought conditions deteriorated in the northern Rockies and adjacent High Plains, The Texas Panhandle, and a few patches across the Southeast.
Moving forward, the large area of drought covering much of the western half of the country is expected to generally persist, with areas of intensification possible. In addition, drought is expected to expand eastward into the south-central Plains, where odds favor below-normal March-May precipitation and a return to warmer than normal conditions. The only area in the West where drought should ease extends from southwest Oregon to central Washington. Outside this extensive area of drought area, only small, isolated locales are impacted by drought. The scattered patches across the Southeast should be approximately the same at the end of May, though precipitation in the short-term may provide limited relief for the time being. Meanwhile, drought is expected to develop across much of the Florida Peninsula, where moisture deficits have been increasing and odds favor a warm and dry March-May, which is typically one of their drier seasons in any case. Across the remainder of the country, the small regions of drought in northern New England, the Midwest, Hawaii, and Puerto Rico should improve or be removed by the end of May.
Forecaster: Richard Tinker
Next Seasonal Drought Outlook issued: March 18, 2021 at 8:30 AM EST.
Seasonal Drought Outlook Discussion