[Excerpt from the May 28th U.S. Drought Monitor]

During this U.S. Drought Monitor (USDM) week, a strong high pressure ridge was anchored over the southeastern contiguous U.S. (CONUS) while an upper-level trough dominated the West. This pattern set up a southwesterly flow across the central part of the country, which funneled moist and unstable air from the Gulf of Mexico into the Plains. Pacific weather systems moving in the jet stream flow plunged into the western trough, bringing precipitation and cooler-than-normal temperatures to much of the country from the Rockies westward.

The weather systems intensified as they moved into the Plains, triggering another week of severe weather and heavy flooding rains. Two or more inches of precipitation occurred across the Plains to Midwest and in upslope areas of Montana and Wyoming, with locally 5 inches or more. Weekly precipitation was wetter than normal across much of the Southwest, and from much of the Great Plains to Great Lakes. Half an inch to locally 2 inches was observed from the central Appalachians to New England, but these amounts were mostly below normal. The week ended up drier than normal across western Washington, northern Idaho and northern Montana, southern Arizona, most of New Mexico, and central to southern Texas. The subtropical high kept the Southeast drier and warmer than normal, with record high temperatures reported.

As a result of this weather pattern, drought contracted in Oregon, Wyoming, and the central Plains, but expanded in the northern Rockies, Texas, the Tennessee Valley, and the Southeast.

The percentage of cattle, corn, and hay in drought continues to remain low at 1% cattle, 1% hay, and no corn areas considered in drought.