Hurricane Laura brings wind, heavy rain to South, while severe to extreme drought persists in West

The big weather news this past week surrounded the rain and wind from Hurricane Laura as it pushed through the lower Mississippi Valley, then northeastward south of the Ohio River to the central Appalachians. Southwestern Louisiana was most severely impacted. Winds gusted to 135 mph in Lake Charles, Louisiana, before the anemometer failed.

Rains totaled 5 inches to locally over a foot along central and western Louisiana, adjacent Texas, much of Arkansas, and southeastern Oklahoma for the 7-days ending Tuesday morning. Other areas accumulating more than 4 inches included parts of Alabama and Mississippi (especially in the northern reaches) and scattered sections of the central Appalachians and eastern Ohio Valley, central Wisconsin, the western Florida Peninsula, and part of interior North Carolina. In contrast, little or no precipitation fell on most of the Carolinas and eastern Georgia, the upper Midwest, most of the central and southern Plains, and from the central Rockies to the Pacific Coast.

High Plains

Between 0.5 and 2.0 inches of rain fell on parts of the Dakotas, much of Minnesota, and central to southwestern sections of Kansas. Several tenths of an inch at best fell elsewhere. As a result, some improvement was noted in parts of eastern South Dakota and west-central Kansas, but dryness and drought persisted or intensified elsewhere. Deterioration was most widespread from central and southern Wyoming eastward through Nebraska as the effects of several weeks to a few months of drier and warmer than normal conditions are taking their toll. As a result, most of Colorado and the central and eastern parts of Wyoming are enduring severe to extreme drought, along with the Nebraska Panhandle and parts of southwestern Kansas and the eastern half of Nebraska.

South

Thanks in large part to Hurricane Laura, only patchy D0 conditions exist from central Oklahoma and eastern Texas eastward despite temperatures averaging 3 to 7 degrees above normal this past month. In contrast, serious drought is plaguing western Oklahoma and the central and western portions of Texas, with small areas of exceptional drought (D4) just south of the Texas Panhandle and over the interior Big Bend region. Precipitation shortfalls of 4 to 6 inches for the past 60 days—and 6 to 8 inches for June-August—cover parts of the Big Bend. Two- to five-inch deficits for the past 60 days were measured in the rest of central and western Texas, while June-August totals 4 to 6 inches less than normal affect most of central Texas and parts of western Oklahoma.

Midwest

Southern and western parts of the region fared much better than other areas. Dryness and drought decreased in a strip across central Wisconsin and southern Michigan, as well as large sections of Ohio. In contrast, drought expanded and deteriorated from central and southern Iowa eastward into northwestern Indiana. A sizable area in central and southwestern Iowa (where extreme drought expanded) received 6 to 10 inches less rain than normal during June-August while adjacent moderate to severe drought areas recorded shortfalls of 3 to 6 inches. Further, hot weather has been common this summer, and temperatures averaged 6 to nearly 12 degrees above normal the last two weeks, exacerbating the effects of the dryness and stressing some crops.

West

Little or no rain was observed region-wide this past week. This is a relatively dry time of year in many areas, especially in California, but a weak monsoon season and periods of excessive heat have led to widespread severe to extreme drought in a large area covering northern and eastern New Mexico and most of Arizona, Utah, Nevada, northern California, Oregon, and central Washington. Only eastern and western Washington, central Idaho and the Panhandle, central and west-central Montana, southwestern California, and part of central New Mexico are free of dryness and drought as of this writing. Wildfires continued to scorch parts of the region, although fires spread more slowly recently in northern California than during the prior few weeks.