A cold front approached the Eastern Seaboard early in the drought week, which drove Tropical Storm Maria farther away from the mid-Atlantic coast, keeping substantial impacts to a minimum. About the same time, the western edge of this cold front moved through southern Texas and New Mexico, bringing significant upslope precipitation (0.5-3.0 inches, locally greater) to the southern Great Plains and adjacent Rockies. Another cold front then moved southeastward out of central Canada, accompanied by primarily light precipitation (0.75-inch or less) to the Great Lakes region and Northeast. Towards the end of the drought week, yet another cold front progressed eastward across the Rockies, and the northern halves of the Great Plains and Mississippi Valley, bringing 1-2 inches of rain to much of the region.
South Region Summary:
The rapid increase in dryness across eastern Oklahoma, northern and western Arkansas during the past 30-days warranted an expansion of D0 conditions, and the introduction of several areas of moderate drought (D1). The adjusted depiction for this week is based on 30-day and 60-day PNPs, 30-day and 60-day ACIS SPIs, high wildfire potential, soil moisture deficits (1-4 inches) and local expertise. Preliminary data for southeastern portions of Oklahoma suggest this past September could be the driest on record. Generous rains fell over the drier portions of Texas this week, resulting in some improvements in the drought depiction. Light winds helped to minimize wildfire impacts. In northwestern Louisiana, a slight southeasterly shift of the D0 and D1 categories was rendered to the drought depiction. This general area has seen little to no measurable rainfall during the past 30-days, with Shreveport reporting their driest September on record (a trace). In south-central portions of Louisiana, D0 was introduced to account for the increasing dryness. Additional degradation may be needed next week across western Arkansas.
During the upcoming 5-day period (Oct. 5-9), a meandering baroclinic zone is predicted to bring 1-4 inches of rain (locally greater amounts possible) from New Mexico across the south-central Plains, the north-central Mississippi Valley, and Great Lakes region. This may be enough to warrant some improvements across Kansas next week, if this forecast verifies. Across the eastern half of the Gulf Coast region, 2-4 inches of rain are generally anticipated, but these amounts could be exceeded if Tropical Depression 16 (TD-16) moves into that region. As of 2 pm EDT, Oct 4, TD-16 is located near the coast of Nicaragua. This scenario would certainly help with some of the dryness across Alabama.
During the 6-10 day period (Oct. 10-14), odds for above normal precipitation are elevated above climatological odds from about the western slopes of the Appalachians to the Atlantic Coast, and over extreme southern Texas. This would be expected to at least offset additional degradation across this region. From about the Mississippi Valley westward to the Pacific Coast, sub-normal precipitation amounts are favored.
A full report is available at droughtmonitor.unl.edu.