Weather

Heat wave on the Plains; severe storms in the upper Midwest

Across the Corn Belt, thunderstorms are affecting a few Midwestern locations. However, most of the region remains dry, continuing a general pattern that has lasted about 2 weeks. In addition, very hot weather prevails west of the Mississippi River, where Wednesday’s high temperatures should generally range from 95 to 105°F. Corn and soybeans in drier areas of the upper Midwest have been lacking in soil moisture and rainfall during the critical reproductive stage of development.

On the Plains, hot, mostly dry weather prevails. Wednesday will feature a final day of blazing heat across the northern Plains, where high temperatures in South Dakota could approach 110°F. On July 27, daily-record highs in South Dakota included 108°F in Pierre and 107°F in Rapid City—the highest reading in the latter location since August 29, 2012. Meanwhile, afternoon temperatures will approach 100°F on the central and southern Plains, where topsoil moisture remains mostly adequate but has begun to diminish.

In the South, a band of unsettled, showery weather stretches from Texas to the southern Atlantic Coast, despite building heat. Wednesday’s high temperatures should generally range from 90°F (in the cloudier areas) to near 100°F in parts of the Tennessee Valley. Most pastures and summer crops remain in good shape, in part due to abundant moisture reserves.

In the West, an active monsoon circulation continues to produce scattered showers, extending northward from the Four Corners region. Recent and ongoing Southwestern rainfall has greatly improved the short-term drought situation; however, underlying long-term issues—such as low reservoir levels—persist. Parts of the Pacific Coast States and northern Rockies have benefited in recent days from lower temperatures and a few showers, but some Northwestern thunderstorms continue to spark new wildfires and produce erratic winds in the vicinity of existing fires.