Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 359 PM EDT Wed Jul 29 2020 Valid 00Z Thu Jul 30 2020 - 00Z Sat Aug 01 2020 ...Heavy rainfall & flash flooding potential across portions of the Plains, Middle Mississippi Valley, and Tennessee Valley through the remainder of the week... ...Searing heat in the West both Thursday & Friday, elevated fire weather risk in the Northwest on Thursday; hot Thursday in the Northeast... ...Potential Tropical Cyclone Nine expected to track through the Greater Antilles the second half of the week... A series of frontal boundaries and an upper level trough will become responsible for an onslaught of heavy rainfall and thunderstorms from the central High Plains to the central Appalachians through Friday. This evening, a stalled frontal over the Ohio Valley and another one over the Midwest look to generate areas of showers and storms over the Nation's Heartland this evening. Slight Risks for both severe storms and flash flooding have been posted in parts of the Central Plains and Middle Mississippi Valley. By Thursday, the upper level trough makes its way over the Central Plains with the stalled front over the Ohio Valley making little effort to exit the region. This means more heavy rain and thunderstorms across the east-central U.S. and southern Appalachians. A slight risk for flash flooding is forecast in these areas along with a continued chance for severe storms. By Friday, the front over the Ohio Valley sags south into the Mid-South where more rounds of heavy showers are on tap along with the concerns for flash flooding and severe storms. A cold front passing into the Southern Plains may also trigger some strong-to-severe storms across the region Friday evening. Cooler than normal temperatures are expected across the Central Plains the remainder of the week. Sizzling heat has taken hold of the Northwest, Great Basin, and Southwest with afternoon temperatures soaring into the triple digits across the interior valleys on Thursday and Friday as a large upper level ridge strengthens across the western states. Record high temperatures are possible and excessive heat warnings are in effect across portions of these regions along with heat advisories in Southern California. In addition, the Storm Prediction Center is concerned about dry thunderstorms forming in the Northwest that would lead to a risk of fire weather due to their associated lightning and lack of rainfall on this evening and Thursday. Red flag warnings remain in effect for this area. Abnormally hot conditions are also expected to stick around the Northeast through Thursday before a cold front ushers in slightly cooler conditions for Friday. All eyes remain fixed on Potential Tropical Cyclone Nine in the eastern Caribbean Sea this afternoon as it tracks towards the Greater Antilles later this week. Showers and thunderstorms associated with this system could reach parts of South Florida by the start of the weekend. Please visit the National Hurricane Center for the latest advisories on Potential Tropical Cyclone Nine. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php