Map data released Sept. 12, 2019 | Data valid Sept. 10, 2019
Current Conditions: Fortunately for the Southeast, Category 5 Hurricane Dorian stalled just east of Central Florida, slowly weakened, and gradually turned northward, finally accelerating northeastward into Nova Scotia and Newfoundland. Its only U.S. landfall was at Cape Hatteras. Unfortunately, it stalled over the northern Bahamas for 1-2 days, devastating the islands of Great Abaco and Grand Nassau. Rainfall from Dorian was limited to coastal sections of eastern Florida, the Carolinas, Delmarva Peninsula, Cape Cod, and extreme eastern Maine. Between 5-10 inches of rain, locally to 15 inches, fell along coastal northeastern South Carolina and eastern North Carolina, although the totals sharply dropped off to the west. A second tropical system, Tropical Storm Fernand, made landfall in northeastern Mexico, but its outer bands of rain brought welcome rains to southern Texas. Frequent cold fronts raced across the northern tier of States, dropping light to moderate precipitation on the Northwest, northern Rockies and Plains, Midwest, upper Great Lakes region, and northern New England. Monsoonal moisture produced light showers in western Texas, Central New Mexico, Colorado, and into Wyoming and Idaho. Dry weather prevailed in western sections of the Southwest, south-central Plains, lower Mississippi Valley, and across much of the Southeast, eastern Ohio Valley, and mid-Atlantic. Temperatures averaged above-normal across the West, southern two-thirds of the Plains, and across the Southeast, with subnormal readings confined to the northern Plains, upper Midwest, Great Lakes region, and Northeast.
South: Mostly dry and warm weather enveloped much of the South, contributing to a rapid decline in short-term moisture conditions across most of Texas, southwest and southeast Oklahoma, southwest Arkansas, and northwest Louisiana. Even a few pockets of D0 were introduced in formerly wet central and northeastern sections of Tennessee. The few exceptions to this were outer bands of rain across southern Texas from Tropical Storm Fernand (which made landfall in northeastern Mexico), some light monsoonal showers in southwestern Texas and the northern Texas and Oklahoma Panhandles, and Day 7 thundershowers in northern Louisiana and central Arkansas. A general 1-category improvement was made across southern Texas in response to 1-3 inches (locally 5 inches) of rain, while some slight improvements were made around the Midland area, Trans Pecos region, and in extreme northern Louisiana. In contrast, September’s climatologically higher rainfall totals for Texas and Oklahoma make degradation faster, and temperatures have remained high. Where little or no rain fell, a 0.5-1 category downgrade was made, especially in central Texas, but also in southwest and southeast Oklahoma, and bordering sections of Arkansas and Louisiana. According to USDA, percentages for both topsoil and subsoil moisture for Texas stood at 85 and 79%, respectively, as of Sep. 8, while topsoil moisture grew increasingly short to very short in Arkansas (67%), Louisiana (60%), Mississippi (66%), and Tennessee (52%). Even with the USDA topsoil moisture figure, Mississippi remained D0-D4 free as the entire state still had 60-day precipitation surpluses. Texas pasture and range conditions have been affected by the warmth and dryness, with 48% rated poor or very poor according to the Sep. 8 USDA/NASS report.
Looking Ahead: During the next 5 days (Sept. 12-16, 2019), the possible development of a tropical system in the western Caribbean and eastern Gulf of Mexico brings enhanced rainfall to the central and eastern Gulf and southern Atlantic Coasts. Elsewhere, the Pacific Northwest should see continued precipitation (0.5-2 inches), while more systems bring rainfall (1-3 inches) to the northern Plains, upper Midwest, and Great Lakes region. Some monsoonal showers should develop in New Mexico and West Texas, with this moisture merging with a cold front that should produce thunderstorms across the south-central Plains. Little or no rain is expected in California, Nevada, most of Arizona, southern Utah, from northeastern Texas eastward to South Carolina, and along coastal New England. Most of the lower 48 States should record above-normal temperatures.
The CPC 6-10 day outlook (Sept. 17-21, 2019) favors above-normal precipitation chances for most of the contiguous U.S. and Alaska, with below-normal odds limited to States along the Northeast Coast. Temperatures are likely to be subnormal from the Rockies westward, while above-normal readings are expected east of the Rockies, especially in the northeastern quarter of the Nation.