Across the Corn Belt, showers and a few thunderstorms are spreading across southern production areas, mainly from Missouri to Ohio. Showers are also occurring in the upper Great Lakes region. Following last week’s downpours, wetness and fieldwork delays continue to plague portions of the eastern Corn Belt. On May 24, topsoil moisture rated surplus ranged from 40 to 56% in Illinois, Indiana, Michigan, and Ohio.
On the Plains, mostly dry weather favors fieldwork and crop development. A few showers linger, however, across the southeastern Plains. Farther west, drought is maintaining stress on rangeland, pastures, winter wheat, and spring-sown crops across portions of the central and southern High Plains. In Colorado, where 39% of the winter wheat was in very poor to poor condition on May 24, topsoil moisture was rated 61% very short to short.
In the South, recently formed Tropical Storm Bertha—located about 30 miles east-southeast of Charleston, South Carolina, early Wednesday morning—is producing locally heavy showers in the Carolinas. Meanwhile, a low-pressure system over the mid-South is sparking showers and slowing fieldwork across a broad area, including the Mississippi Delta. On May 24, topsoil moisture was rated more than 40% surplus in Arkansas (48%), South Carolina (46%), and Tennessee (41%).
In the West, dry weather accompanies building heat. Wednesday’s high temperatures will exceed 105º in parts of California’s Central Valley and could approach 120º in the hottest Southwestern deserts. Rivers across the northern Intermountain West are running swiftly due to melting of high-elevation snowpack. Meanwhile, drought remains a concern in parts of the Northwest, including Oregon, where 25% of the winter wheat was rated in very poor to poor condition on May 24.
Tropical Storm Bertha will drift northward, moving inland later Wednesday across the Carolinas. Storm-total rainfall could reach 2 to 4 inches or more across the Carolinas and southwestern Virginia, leading to flash flooding. Farther west, shower activity will gradually shift eastward, with drier air overspreading the Mississippi Valley by Friday and the Ohio Valley on Saturday. Lingering showers along the Atlantic Seaboard should end by Sunday. Most of the West will experience hot, dry weather during the next several days, except for some weekend showers and cooler weather in the Pacific Northwest. Cool weather will also develop in most areas from the Plains eastward.
Looking ahead, the 6- to 10-day outlook calls for the likelihood of above-normal temperatures throughout the nation’s mid-section, while cooler-than-normal conditions will cover the East and much of the Far West. Meanwhile, above-normal precipitation in the West, southern Texas, and across the nation’s northern tier as far east as Lake Superior should contrast with drier-than-normal weather from the central and southern Plains to the East Coast.