Map released May 14, 2020 | Data valid: May 12, 2020
This week’s drought summary: Light precipitation at best covered most of the 48 states, so drought deterioration was more common than improvement this past week. Less than half an inch fell on most areas across the Southeast, Great Lakes Region, central and northern Plains, Mississippi Valley, Texas, and from the Rockies to the Pacific Coast. Widespread light to moderate precipitation covered the Northeast and the central Appalachians, and a fairly broad area centered along the Ohio Valley received from a few tenths to one-half inch. Farther west, there were a few exceptions to the generally dry week. More than two inches of rain soaked parts of the south-central Great Plains and adjacent western Mississippi Valley, western Deep South Texas, and central Montana. The broadest area of heavy precipitation covered a solid swath from South-central Kansas through South Missouri, where totals ranged from two to nearly four inches. Similar amounts were more scattered in a stripe from southern Oklahoma and northeastern Texas through southern Louisiana, as well as in central Montana. Isolated sites in southwestern Texas were soaked by as much as six inches of rain, but closer to two inches fell on most locales there. Elsewhere, there were a few areas of moderate to precipitation from the northern High Plains into central Montana, and in orographically-favored parts of the northern Cascades.
South: Similar to conditions in the Southeast, surplus rainfall has prevailed across the interior, but dryness and drought are entrenched along most of the Gulf Coast, and across South Texas. Less extreme dryness covers part of Central Texas, Western Oklahoma and adjacent Texas, and the lower Big Bend. D0 prevails across these regions, with only scattered patches of moderate drought. In contrast, extreme D3 drought has developed in a few regions across South Texas, primarily near the Gulf of Mexico and along the Rio Grande, while severe drought is impacting a large part of southeastern Texas and smaller areas near the Mexican Border. A small area of intense rainfall – up to five inches in spots – brought relief to western Deep South Texas, with the wettest areas improving from severe D2 drought to abnormal dryness (D0). Areas of severe to extreme drought recorded less than half of normal rainfall for the past 90 days, with rainfall deficits of five to seven inches observed southeast of Victoria.
Looking Ahead: During May 14-18, 2020, a broad swath of heavy rain is expected from south Texas northeastward across Missouri, the northern Ohio Valley, the Northeast, and lower New England. Forecasts show a broad, unbroken stripe through this region where more than 1.75 inches of precipitation is expected. Within this stripe, some areas are expecting very heavy precipitation. Most notably, Central to South Texas is expecting thre to locally five inches of rain. A few smaller patches are expected to get three to maybe four inches of rain, including Northeast Oklahoma and Southeast Kansas, part of North-Ventral Illinois, and Northwestern Pennsylvania and adjacent Ohio to near Cleveland. Outside this stripe, precipitation will drop off dramatically.
From the Carolinas through Alabama and into Central Florida, almost no rain is anticipated. Likewise, precipitation should be lacking from the Great Basin and Southern California through most of the Four Corners States.
Elsewhere, moderate to heavy precipitation is expected in orographically-favored areas near the Sierra Nevada and Cascades, and in South Florida (especially along the southeastern coastline). Light to moderate precipitation, with totals approaching an inch in a few patches, are expected from the upper Mississippi through the north half of the High Plains to the Pacific Northwest. Most of the 48 states will stay warmer than normal at night, save for upper New England. But temperatures should remain unusually low during the day across the Great Lakes into the Northern Plains, and from Central California through the Pacific Northwest. Other areas should average a few degrees above normal at night, and near normal during the day.
For the ensuing five days, drier than normal conditions are favored from roughly from the Mississippi Valley through the Atlantic Seaboard, and to a lesser extent in parts of the Central Rockies and surrounds. There are enhanced chances for surplus precipitation across most of Texas into Central New Nexico, across the northern tier of states from the Plains westward, and over the Great Basin and nearby California. Meanwhile, in most locales from the Plains (outside South Texas) eastward across the Mississippi Valley to the Appalachians, odds favor above-normal temperatures. Farther west, subnormal temperatures are favored from the western Rockies to the Pacific Coast.