In the West, an active monsoon circulation is resulting in scattered showers, mainly in the Four Corners States. Cooler air is overspreading the Northwest, although a significant threat of wildfire development or expansion still exists in parts of the northern Intermountain West.
On the Plains, beneficial but widely scattered showers continue across roughly the southern half of the region. Farther north, cooler air is beginning to overspread Montana’s High Plains, but hot, mostly dry weather favors late-season small grain harvesting and other fieldwork elsewhere on the northern Plains.
In the Corn Belt, isolated showers are confined to the upper Midwest. Elsewhere, late-season heat is bringing renewed stress to pastures and immature summer crops, following a 2-week period of favorably cooler weather.
In the South, scattered showers linger along the southern Atlantic Coast and are developing in the western Gulf Coast region. Elsewhere, warm, dry weather favors late-summer fieldwork, including corn and rice harvesting.
Outlook: During the next several days, the interaction between the Southwestern monsoon circulation and disturbances crossing the Plains and Midwest will result in significant rainfall (possibly 2 to 4 inches, with locally higher amounts) from the central and southern Plains into the middle Mississippi Valley. Farther west, mostly dry weather will persist in California and the Northwest. Most of the nation will continue to experience near- to abovenormal temperatures, and hot weather will return to the Northwest during the weekend. In the tropics, Isaac will become a threat to the southeastern U.S. early next week, although the storm’s exact track remains uncertain. In addition, Isaac’s interaction with Hispaniola and Cuba will help to determine its strength upon arrival in the U.S. The NWS 6- to 10-day outlook for August 29 – September 2 calls for near- to above-normal temperatures nationwide, except for cooler-than-normal conditions along and near the Pacific Coast. Meanwhile, near- to below-normal rainfall across most of the U.S. will contrast with wetter-than-normal weather in the Southeastern and Mid-Atlantic States and parts of the northern Plains.