Map released Sept. 24, 2020 | Data valid Sept. 22, 2020
This week’s drought summary: Category 2 Hurricane Sally made landfall on Sept. 16 near Gulf Shores, Alabama, around 4:45 a.m. CDT, with sustained winds near 105 mph. Torrential rainfall across southern Alabama and western Florida sparked major to record flooding, while wind-related damage and power outages were common. Once inland over the Southeast, Sally quickly weakened but continued to produce heavy rain, extending as far north as southern Virginia. Mostly dry weather covered the remainder of the country, except for showers in the Pacific Northwest and heavy rain in the western Gulf Coast region associated with the arrival of Tropical Storm Beta along the middle Texas coast. Beta, the 23rd named storm of the Atlantic hurricane season—behind only 28 tropical cyclones in 2005—made landfall at 10 p.m. CDT on Sept. 21 near Port O’Connor, Texas, with sustained winds near 45 mph. Meanwhile, drought remained entrenched across much of the western half of the country and parts of the Northeast. In the latter region, growing season-ending freezes (starting Sept. 19) may limit re-growth of drought-stressed pastures, even if widespread precipitation returns during autumn. Western wildfires continued to degrade air quality across a vast area, with approximately six dozen fires in various stages of containment by Sept. 22.
South: Tropical Storm Beta made landfall on Sept. 21 along the middle Texas coast, resulting in eradication of dryness (D0) and moderate drought (D1) in the western Gulf Coast region. Torrential rain fell mainly north of Beta’s center of circulation, including parts of the Houston metropolitan area. Numerous reports of at least 10 inches of rain were received from Harris County, where Houston’s William P. Hobby Airport netted 12.24 inches from Sept. 20-22.
Farther inland, additional improvements were introduced across Central Texas in the wake of last week’s heavy rain, as drought impacts further faded.
Meanwhile, a pesky area of dryness (D0) and moderate drought (D1) remained centered over Mississippi, with some further intensification noted. On Sept. 20, USDA topsoil moisture in Mississippi was rated 56% very short to short. Sept. 1-22 rainfall totals in Mississippi included 0.10 inch (5% of normal in Vicksburg and 0.22 inch (9%) in Meridian. (Sept. 23-24 rainfall in Mississippi and neighboring states associated with the remnants of Beta fell too late to be considered for this week’s report.)
Elsewhere, ongoing dry weather in western sections of Texas and Oklahoma led to some modest expansion of dryness (D0) and moderate to extreme drought (D1 to D3). For the year-to-date through Sept. 22, precipitation in Midland has totaled just 6.84 inches (62% of normal). Dalhart is faring about as poorly, with 8.81 inches (60% of normal) falling from Jan. 1 to Sept. 22. The Vegetation Health Index (VHI) indicates that rangeland and pastures are significantly stressed across large sections of the southern High Plains, including much of West Texas.
Looking ahead: The remnants of Tropical Storm Beta will drift generally northeastward and continue to weaken, although additional Southeastern rainfall could total three to five inches or more. Meanwhile, a series of cold fronts will cross the Midwest, generating scattered showers. Some of the most significant rain, one to two inches over the next five days, should fall in the vicinity of the Great Lakes. Farther west, mostly dry weather will continue during the next five days from California to the Plains and middle Mississippi Valley. In the Northwest, however, frequent showers—especially west of the Cascades—should provide relief from a dry summer and aid wildfire containment efforts. Aside from a surge of cool air into the Northwest, much of the country will experience near- or above-normal temperatures during the next several days.
The NWS 6- to 10-day outlook for Sept. 29 to Oct. 3 calls for the likelihood of above-normal temperatures in Maine and throughout the West, while cooler-than-normal conditions will cover most of the eastern half of the country. Meanwhile, near- or below-normal precipitation across most of the nation should contrast with wetter-than-normal weather in South Florida and from the Great Lakes region into the northern and middle Atlantic States.