407 FXUS01 KWBC 130821 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 420 AM EDT Mon Jul 13 2026 Valid 12Z Mon Jul 13 2026 - 12Z Wed Jul 15 2026 ...Anomalous heat and humidity continue across the northern Plains to the upper Midwest, spreading into the Northeast by Tuesday... ...Threat of heavy rain gradually abates across the southern Appalachians to the Carolinas as a heavy rain event emerges across the Hill Country to the Big Bend regions of Texas... A strong upper-level high is forecast to build eastward across the northern tier states toward New England over the next couple of days. The anomalous heatwave underneath this high resulted in all-time record high temperatures across portions of the Great Basin to the northern High Plains on Sunday. As the high builds eastward, triple-digit high temperatures will be widespread across the northern Plains over the next couple of days, as heat soaring well into the 90s spreads into the upper Midwest today before reaching the Great Lakes and the Northeast on Tuesday along with increasing humidity. Extreme Heat Warnings remain in effect across a large portion of the Great Basin through the northern Plains as Extreme Heat Watches and Heat Advisories are posted for areas farther east into New England. If you will be situated within any of these areas forecast to experience extreme heat, stay hydrated, take frequent breaks and limit outdoor activities if possible. A cold front will draw slightly cooler air eastward from the Pacific Northwest into Montana and North Dakota over the next couple of days dropping high temperatures into the 90s. South of this anomalous upper high, a front is forecast to remain nearly stationary through the southern Plains, the Deep South and the Southeast. Upper-level disturbances will then interact with the wavy stationary front to produce repeated rounds of showers and thunderstorms across this corridor of the southern U.S. Meanwhile, the heavy rain threat from the southern Appalachians to the Carolinas early today will gradually abate as drier air filters in from the north. On the other hand near the western end of the front, a heavy rain event is forecast to emerge across the Hill Country to the Big Bend regions of Texas over the next couple of days where clusters of thunderstorms could mutually amplify the aforementioned upper-level disturbances to result in additional heavy rainfall. Please stay tuned to future updates on this upcoming heavy rain event. Farther west, an influx of monsoonal moisture will lead to an uptick in daytime thunderstorms over portions of the Great Basin and Intermountain West, which could lead to a few instances of flash flooding and severe weather through at least midweek. Kong Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$