According to the National Drought Monitor, drought covers 64.09% of the contiguous U.S., which is up slightly from last week. But slight drought relief was seen across the Midwest, with 43.22% of the area now free of drought, which compares to 48.43% last week. However, drought spread slightly across the South, with 84.14% of the region covered by some form of drought, which compares to 81.14% last week.
For the Midwest, the monitor notes that after several weeks of rapid deterioration due to "flash drought" conditions in the Midwest (lack of rain + heat), this week finally brought some relief with lower temperatures and light to moderate rain via two separate cold fronts. "Locally heavy rains (1.5 to 3 inches) that fell across west-central Minnesota was enough to remove the D0 there, and 2-weeks of moderate rains in west-central Illinois reduced shortages enough to improve to D0," it notes. "The widespread 0.5 to 1 inches of rain that occurred elsewhere was enough to prevent further deterioration, but not enough to significantly dent the 90-day accumulated deficits. In contrast, rainfall amounts diminished across southern sections of the Midwest, with weekly totals under 0.5 inches. With increasing deficits at 60- and 90-days, abnormal dryness was expanded across most of Indiana, southwestern Ohio, and southern Illinois. D1 similarly increased near St. Louis, MO area, central Illinois, and central Indiana. 60- and 90-day deficiencies have reached 3-6 and 4-8 inches, respectively, in the aforementioned D1 areas."
The monitor notes that after a relatively wet June (and spring), the summer months (Jun-Aug) were ranked as the 13th, 32nd and 36th driest since 1895 (119 years) for Iowa, Minnesota and Illinois, respectively, according to NCDC, "depicting how dry July and August were. Fortunately, summer temperatures averaged below normal," it adds.
Across the Southern Plains, the monitor notes that general improvements were made in western sections of Oklahoma and Texas, while eastern portions deteriorated. In the Oklahoma Panhandle, copious monsoonal rains that inundated parts of the Southwest and central Rockies and caused flash flooding also soaked the extreme western Panhandle (and southeastern Colorado) with over 5 inches of rain, enough for a 2-category improvement to D1. "With lesser totals (1.5 to 3 inches) just to the east, a 1-category improvement was made to the rest of the Oklahoma Panhandle and in northwestern Oklahoma. Similarly, 2 to 4 inches of rain along the KS-OK border was enough to erase D0 in Kay and Osage counties. However, little or no rain along the Red River Valley continued the dry trend in southern sections of the state as D2 and D3 expanded in extreme southern Oklahoma and across much of eastern Texas (and Louisiana)," it states.
Along the Kansas border and in the extreme southwestern and far western areas, rainfall amounts exceeded 2 inches for the period, allowing for some slight drought reductions to be made. "In Kansas, heavy rains (more than 2 inches) fell across the northern half of the state, with up to 7 inches falling in the northwestern corner, while decent rains also occurred in western and southern sections. As a result, D4 was eliminated from Kansas (to D3) while a reduction in the eastern D0-D3 edges were made. The D0 edge in eastern and southern Kansas was also pared back. Some small 2-category improvements were done in northwestern Kansas in association with the heaviest rains," it states.
In its outlook for September 19-23, a slow-moving frontal system will trigger showers and thunderstorms from the Great Plains eastward to the Atlantic Coast, with the largest totals (more than 1.5 inches) expected along the Rio Grande Valley eastward along the Gulf Coast and into the Southeast. "An inch of rain is also forecasted from the central Great Plains northeastward into the upper Great Lakes region, with unsettled weather returning to the Pacific Northwest. Much drier weather should return to the Southwest, central Rockies, and High Plains, allowing for recovery from flooding. Temperatures should average above normal across the contiguous U.S. except for subnormal readings in the Far West," it states.