In the Corn Belt, a band of rain — heaviest in the lower Great Lakes region — separates very cool air across the upper Midwest from lingering warmth in the Ohio Valley. The cool conditions are a concern with respect to corn and soybeans, many of which are running out of time to fully mature.
In addition, parts of the northern Corn Belt have become very wet, with topsoil moisture on Sept. 29 rated more than one-third surplus in Minnesota, Wisconsin, and North Dakota.
On the Plains, cool air is driving southward, but warmth lingers primarily across Oklahoma and Texas. Snow showers prevail across the northern Plains, while patchy rain is affecting the remainder of the region. Despite recent and ongoing rainfall, some drought persists in Texas, where topsoil moisture on Sept. 29 was 64% very short to short.
In the South, relentless late-season heat and dryness are further stressing pastures. In addition, there is little topsoil moisture for the germination and establishment of fall-sown crops, while surface water supplies (e.g., stock ponds) are beginning to dry up in some areas. On September 29, topsoil moisture was rated at least 60% very short to short in all Southeastern States except Florida.
In the West, freeze warnings were in effect again early Wednesday in several areas, including portions of the Snake River Plain. In fact, cool weather throughout the Northwest is slowing the emergence and growth of recently planted winter wheat. Dry weather prevails elsewhere, except for a few snow showers in the northern Rockies and some rain in southeastern New Mexico.
Summerlike heat will continue for a few more days across the South, although markedly cooler air will encroach from the north and west. By Friday morning, a high-pressure system centered over the upper Great Lakes region could lead to widespread frost and scattered temperatures near the freezing mark in the upper Midwest.
Meanwhile, mostly dry Southeastern weather will likely lead to further drought intensification and increasing impacts on pastures, fall-sown crops, and surface water supplies. Farther north and west, however, periods of rain will occur during the next five days from the southern Rockies into the Northeast. Rainfall could total 1 to 3 inches or more across the east-central Plains and upper Midwest.
Elsewhere, rain and snow showers will end later Wednesday across the northern Plains, followed by the late-week arrival of scattered shows in the Northwest.
Looking ahead, the 6- to 10-day outlook calls for near- or above-normal temperatures nationwide, except for cooler-than-normal conditions in parts of the Northwest. Meanwhile, near- or below-normal precipitation across much of the western and central U.S. should contrast with wetter-than-normal weather in the East and Pacific Northwest.