In the West, a late-season surge of monsoon moisture is resulting in an increase in showers in the Desert Southwest. Elsewhere, mostly dry weather favors fieldwork, although cooler air is overspreading the Pacific Northwest.
On the Plains, late-season heat has returned, following a brief spell of cooler weather. Today’s high temperatures will approach 100°F as far north as South Dakota. Hot weather and significant soil moisture shortages are making some producers reluctant to move ahead with winter wheat planting preparations.
In the Corn Belt, cool, dry weather prevails in the wake of recent rainfall. Drought-easing rainfall was heaviest across central and southern Indiana, where late-week and weekend precipitation totaled 4 inches or more in many locations. Meanwhile, breezy conditions are developing across the upper Midwest, signaling the imminent return of warm weather.
In the South, mild, dry weather prevails, except for isolated showers across Florida’s peninsula. Dry weather is promoting an acceleration of fieldwork—including summer crop harvesting—in the Southeast, following recent heavy rainfall.
Outlook: Warm weather will soon return to the Midwest, South, and East, but another surge of cool air will arrive across the Plains and upper Midwest by September 12-13. By week’s end, the weather pattern will repeat, with cooler conditions spreading across the Midwest, South, and East, and warmth returning to the northern Plains and upper Midwest. Meanwhile, a surge of monsoon-related moisture will be drawn across the central and southern Plains and parts of the Midwest in advance of a cold front. Five-day rainfall totals could reach 1 to 2 inches, with locally higher amounts, from the Southwest into the Great Lakes region. The NWS 6- to 10-day outlook for September 15-19 calls for below-normal temperatures across the nation’s mid-section, including the Plains and the Mississippi Valley, while warmer-than-normal weather will prevail along the East Coast and west of the Rockies. Meanwhile, below-normal precipitation from the Mississippi River westward will contrast with wetter-than-normal conditions across the eastern one-third of the U.S.