Heat wave on the central, southern Plains; storms, locally severe & heavy rainfall for parts of the Corn Belt
Across the Corn Belt, a cold front is producing showers and thunderstorms from the Great Lakes region into the middle Missouri Valley. In advance of the front, Wednesday’s high temperatures should range from 90 to 100°F, accompanied by high humidity levels. Meanwhile, slightly cooler air is overspreading the upper Midwest. In parts of the Corn Belt, significant, short-term rainfall deficits have developed in recent weeks. For example, rainfall in Des Moines, Iowa, totaled just 0.20 inch in the 27-day period from July 7 – August 2.
On the Plains, slightly cooler air is overspreading the northern half of the region, following Tuesday’s extreme heat. Daily-record high temperatures for August 2 included 109°F in Valentine, Nebraska, and 105°F in Sioux Falls, South Dakota. Early Wednesday, a few showers and thunderstorms—mainly across Kansas and Nebraska—accompany the transition to cooler conditions. Extremely hot weather prevails, however, across the southern half of the Plains. On July 31, Texas led the U.S. in very poor to poor ratings for rangeland and pastures (91%), corn (50%), and sorghum (48%).
In the South, scattered showers stretch from the central Gulf Coast region into the southern Atlantic States. Meanwhile, hot, humid weather prevails from the western Gulf Coast region to the Mississippi Delta. High temperatures will again reach 100°F or higher in much of eastern Texas, except along the Gulf Coast.
In the West, rain associated with the Southwestern monsoon circulation has temporarily waned, although a few showers linger mainly in the Four Corners States. Although slightly cooler weather has arrived in the Northwest, temperatures remain mostly at above-normal levels. In addition, the Northwestern wildfire threat remains significantly elevated due to gusty winds, low humidity levels, and the potential for dry thunderstorms.