Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Tue Aug 12 2025 Valid 12Z Tue Aug 12 2025 - 12Z Thu Aug 14 2025 ...Scattered thunderstorms will persist across the Southeast and into southern Appalachians... ...Thunderstorms across the south-central Plains are expected to become less intense and more scattered today before they slide east into the Deep South on Wednesday... ...A couple of days of heat across the Intermountain West as heat builds over the High Plains and the Northeast through midweek... A nearly stationary front extending from the Midwest to the southern Plains has been the focus for repeated rounds of heavy showers and strong to severe thunderstorms for the past few days. The front is forecast to gradually dissipate but upper-level impulses associated with an upper trough can help trigger additional thunderstorms across the south-central Plains today. The thunderstorms are expected to be less intense and more scattered today compared with the past few days. By Wednesday, the front is forecast to further wash out but the presence of upper-level impulses could once again touch off a few more thunderstorms over the south-central U.S. Meanwhile, the better chance for scattered thunderstorms will be farther east by later today across the Deep South, and especially closer toward the Gulf Coast where tropical moisture associated with another dissipating front is forecast to move farther inland across the interior Southeast, the southern to central Appalachians and then up into the interior Mid-Atlantic on Wednesday. A cold front advancing through the Great Lakes will also touch off some thunderstorms Wednesday evening across interior New England. Drier air will begin to reach into the Northeast behind the front on Thursday. While cooler and drier air will at least temporarily spread into portions of the northern Plains to the Great Lakes region behind the aforementioned cold front, it will be quite hot and humid out ahead of these boundaries. Temperatures will be well above normal from the Ohio Valley through most of the Mid-Atlantic and especially the interior of the Northeast, with temperatures locally reaching well into the 90s. Clouds and rain will keep temperatures cooler across the South, but it will be very muggy here given the tropical moisture environment already in place. Across the West, a ridge of high pressure aloft will keep temperatures here quite hot with much above normal temperatures expected through midweek across the Pacific Northwest, Great Basin and into the Desert Southwest. Some of the interior deserts of the Southwest may see high temperatures reach well into the 110 to 120 degree range. Widespread Heat Advisories and Excessive Heat Warnings are in effect as a result. A gradual break in the heat is expected at least across the Northwest by late this week as a cold front arrives and helps to break down the ridge of high pressure. By later on Wednesday into Thursday morning, a low pressure system is forecast to develop over the northern Rockies and northern High Plains. This system will help bring the heat in the western U.S. into the central High Plains on Thursday. In addition, a round of strong to severe thunderstorms is forecast to impact portions of the northern Plains Wednesday night into Thursday morning as the developing low pressure system lifts and interacts with a pair of warm fronts across the northern Plains. Kong/Orrison Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php