This week’s drought summary
A pair of low pressure systems tracked from the Southeast northward along the East Coast, bringing a swath of widespread precipitation (2 to 4 inches, locally more) to much of the East Coast at the end of April. During the final week of April, the Southern Great Plains along with the Lower Mississippi Valley also received widespread precipitation with amounts exceeding 2 inches across southeastern Colorado, northern and eastern Oklahoma, and northeastern Texas. Late April was mostly dry across the Central to Northern Great Plains and Middle Mississippi Valley. Little to no precipitation was observed throughout the West where a significant warmup at the end of April resulted in rapid snowmelt, runoff, and flooding along streams and rivers. In contrast to these above-normal temperatures, cooler-than-normal temperatures occurred across the Great Plains, Corn Belt, and much of the East from April 25 to May 1.
Balancing longer term SPIs and recent widespread rainfall (1 to 3.5 inches), a 1-category improvement was made to parts of Oklahoma and Texas. Improvements were also made to parts of central Texas along with the Texas Gulf Coast after more than 1.5 inches of rainfall this past week. CPC’s leaky bucket soil moisture and 90 to 120-day SPI supported a slight expansion of moderate (D1) to severe (D2) drought in west-central Texas. Based on soil moisture considerations and impact reports (very dry pastures), extreme (D3) drought was increased in coverage across the Texas Panhandle. The addition of abnormal dryness (D0) in east-central Tennessee was based on increasing 30-day deficits, SPEI, soil moisture, and 28-day average streamflows.