797 FXUS01 KWBC 130746 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 345 AM EDT Thu Aug 13 2026 Valid 12Z Thu Aug 13 2026 - 12Z Sat Aug 15 2026 ...Dangerous heat continues from the Central/Southern Plains into the Southeast... ...An active pattern will keep the threat of heavy rainfall/flash flooding in the forecast throughout much of the Midwest and Western U.S... A heatwave has settled in across the Central/Southern Plains and the Southeast as an upper-high strengthens overhead. Forecast highs in the upper 90s to low 100s combined with high humidity will lead to heat indices in the 105-115 degree range. Some potential record-tying/breaking temperatures are possible with many areas forecast to see their hottest temperatures so far this year or even in the past few years. Morning lows only dropping into the mid-70s to low 80s will provide little relief from the heat overnight. Widespread Major to Extreme HeatRisk (levels 3 and 4 out of 4) is expected indicating oppressive heat dangerous to anyone without access to adequate cooling or hydration. Unfortunately, the heatwave is forecast to continue well beyond the current forecast period through at least mid-August. Along the northern periphery of the upper-high, a wavy stationary front will maintain the focus for daily thunderstorms from the High Plains to the Ohio Valley. Widely scattered flash flooding (some of which could be significant) is possible across this broad area as training thunderstorms overlap with areas of increasingly saturated soils from recent heavy rainfall. The severe weather threat with this activity is slightly lower, although isolated to scattered damaging wind gusts will be possible each day. The unsettled weather will also continue along and west of the Rockies as broad upper-troughing siphons Pacific moisture towards the Intermountain West. As such, the greatest coverage of showers and thunderstorms across the West is expected over the next two days with an attendant threat of isolated to scattered flash flash flooding across the Southwest, Great Basin, and Intermountain West. One benefit of the precipitation, however, is that daytime temperatures west of the Continental Divide will be notably cooler than normal for this time of year to provide some relief from the recent heat. Asherman/Putnam Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$