Cool wet weather with heavy to excessive rains expected across portions of the southern plains...
Locally heavy to excessive rains possible across portions of the
central-southern Rockies and Southwest...
Locally heavy to excessive rains possible for portions of the northern
plains and upper Midwest...
Hot and humid with limited chances for rain across much of the eastern U.S....
Cooler temperatures with widespread showers and thunderstorms are expected across the southern plains as an upper low continues its westward journey across the southern U.S. Conditions will become favorable for the development of widespread heavy to locally excessive rains across portions of the region, especially over north-central TX, where the WPC has indicated a moderate risk for excessive rains through Monday afternoon. Heavy to locally excessive rains are also possible during this time further to the west along the eastern front of the CO and NM Rockies and high plains as deeper moisture moves out ahead of this system into the higher terrain.
By Monday evening into Tuesday, the heavy to excessive rain threat will become more centered across west TX from the southern
Panhandle to Big Bend country as the aforementioned low continues to drift west.
Scattered showers and thunderstorms over the Southwest today and Monday will likely become more widespread by Tuesday as moisture traversing the mountains from the east fortifies the monsoonal moisture over the region. Late Monday into Tuesday the WPC has indicated a slight risk for excessive amounts centered over southeastern AZ and southwestern NM.
Across the central-northern plains and upper Midwest, a slow moving
frontal boundary will focus showers and thunderstorms from Neb, the
Dakotas to northern MN today into tomorrow. Fueled by a deep moisture pool along the boundary, some of these storms may produce locally heavy to excessive amounts, particularly from central SD to northern MN where the WPC has indicated a slight risk for excessive rains.
Further to the east, hot and humid conditions, but with limited chances for rain, will prevail across much of the U.S. east of the Mississippi as high pressure shifts westward out of the Atlantic.
An exception is across the Southeast where deeper moisture and mid level impulses moving around the southern periphery of the low may help to generate afternoon and evening thunderstorms.