Summary

May 16, 2019 - Widespread precipitation this week led mostly to improvements in moderate drought and abnormally dry regions across the Southeast and South, and in the Rocky Mountains in southern Colorado and northern New Mexico. In parts of central and western Washington where high evaporative demand and paltry precipitation amounts continued, conditions degraded to moderate drought. Moderate and severe drought continued in southeast Alaska and in parts of Hawaii, while moderate drought and abnormal dryness coverage was adjusted in Puerto Rico.

Northeast

Widespread precipitation occurred in the region over the last week, keeping the region free of abnormal dryness or drought.

Southeast

Moderate to heavy rain engulfed much of the western Florida Panhandle and much of Alabama and southwest Georgia. As a result, short-term precipitation deficits were erased in many areas, leading to the removal of moderate drought that previously had extended from the Mobile area northeastward into southern Georgia. Some areas of abnormal dryness also improved in the Florida Panhandle, Alabama, and Georgia. Moderate drought was also removed in northeast Georgia and adjusted in parts of central and southern Georgia and South Carolina in response to changes in short-term precipitation deficits this week. The rest of the region remained free of abnormal dryness or drought.

South

Rainfall over the region was widespread and heavy in many areas, particularly Louisiana and southeast Texas, and this caused short-term precipitation deficits to improve in Texas and far southern Louisiana. Abnormal dryness in the Texas and Oklahoma panhandles was removed after rainfall this week. Abnormal dryness was also reduced and adjusted in southern Texas in response to recent rainfall. Abnormal dryness also ceased in southern Louisiana where heavy rainfall amounts of 3 to 5 inches were common this week.

Midwest

Light to moderate precipitation occurred over much of the Midwest, which was free of drought or abnormal dryness going into this week, and the region remains free of abnormal dryness or drought.

High Plains

Recent precipitation led to the removal of abnormal dryness in southeast Wyoming. Abnormally dry conditions continued from southwest Nebraska into northeast Colorado. Recent precipitation in the Wind River Range in Wyoming and improving surface moisture conditions led to a reduction of abnormal dryness in this area.

West

Precipitation over the past week in Colorado and New Mexico led to reduction of long-term precipitation deficits and improvement in conditions in southern Colorado and northern New Mexico. Moderate drought was completely removed from southern Colorado, and severe and moderate drought coverage was reduced in northwest New Mexico, where vegetation is prospering. A large area of long-term abnormal dryness also improved to normal conditions in south-central Colorado because of the continued precipitation. Abnormal dryness coverage in southwest Wyoming and northeast Utah was also reduced because of the effects of recent precipitation. Meanwhile, short- and long-term dry conditions, low streamflow, and high evaporative demand continue in western Washington, where moderate drought expanded to cover more of central and western Washington, including the coastal areas of the Olympic Peninsula.

Alaska, Hawaii, and Puerto Rico

Moderate drought continued in central Puerto Rico this week, though coverage was slightly reduced based on the location of short-term precipitation deficits. Abnormally dry conditions also expanded in southwest Puerto Rico. No changes were made this week in Alaska, and severe and moderate drought continued in southeast Alaska. Severe and moderate drought also continued on several islands in Hawaii, and no changes were made there this week.

Pacific Islands

The weather pattern during this USDM week (5/8/19-5/14/19) consisted of a couple weak circulations within a surface or near-equatorial trough across western (Yap State and Palau) to central (Kosrae to Chuuk States) Micronesia, trade-wind convergence over the Marshall Islands (RMI) and Kosrae State enhanced by the circulation (Invest 92W) which slowly moved across the eastern Federated States of Micronesia (FSM), and a dry trade-wind regime continuing across much of northern and western Micronesia. South of the equator, a northwest-to-southeast oriented surface trough remained nearly stationary near the Samoan Islands throughout the week. A surface low developed within the trough near the end of the week. This trough was a manifestation of the South Pacific Convergence Zone (SPCZ), with northerly winds to its north converging with southeasterly winds to its south. Satellite-based estimates of 7-day precipitation (QPE) showed a large area of 2 to 4+ inches of precipitation, with locally 10+ inches, across Kosrae to Pohnpei States associated with circulation 92W which tracked slowly across eastern FSM. A band of 1 to 2 inches of rainfall was indicated across parts of the RMI associated with the trade-wind convergence due to differential wind speeds. Small areas of 1-4 inches of precipitation were seen over parts of Palau and northwestern Yap State. Otherwise, little to no precipitation was indicated on the QPE maps for the rest of Micronesia. In the Southern Hemisphere, a large northwest-to-southeast region of 2-4 inches of precipitation, with locally higher amounts, stretched just north and east of the Samoan Islands, with its southern end engulfing American Samoa.