Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 319 AM EDT Tue Jul 28 2020 Valid 12Z Tue Jul 28 2020 - 12Z Thu Jul 30 2020 ...Heavy Rainfall/flash flooding possible for parts of the Central Gulf Coast, Plains, Midwest, and Tennessee Valley over the next few days... ...Increased Fire Weather danger in and near Oregon Tuesday into Wednesday... ...Cooling trend in the Plains, heat in the Northwest Tuesday & Thursday, hot in the Northeast on Tuesday... Mid-level ridging will give way to broad troughing aloft across the middle of the Lower 48 due to shortwaves moving around a developing/amplifying Western Ridge. Cooler temperatures will move into the central U.S. as an associated cold front moves through the area. Moisture will continue to advect northward into the nation's mid-section, focusing on the front extending southwest from a cyclone in Canada and a more southerly surface trough which will act to focus thunderstorms with heavy rainfall. A Slight Risk for excessive rainfall and localized flooding concerns exists for the Northern High Plains into the Midwest and Southern Plains on Tuesday & Wednesday shifting southeast from the Central Plains into the Tennessee Valley on Thursday as the upper trough slowly shifts east. Heavy rains will linger along the central Gulf coast for another day as an upper level disturbance continues to draw Gulf moisture into the region; flash flood watches are in effect in this area. Across the the Northwest, temperatures will heat up again on Tuesday reaching the 90s to near triple digit high temperatures before a Pacific cold front moves into the area Tuesday night; heat advisories are in effect. The boundary washes out ahead of another system approaching the West from the northeast Pacific, which along with a building mid-level ridge allows the heat to rebuild on Thursday with triple digit/record highs possible across the Southwest, Great Basin, and Northwest. On Tuesday and Wednesday, the Storm Prediction Center has concerns that the thunderstorms in and near Oregon would lead to an increased risk for fire weather due to their associated lightning and minimal expected rainfall; red flag warnings are in effect for portions of Idaho and Oregon in and near the area defined as a Critical Risk for fire weather on Tuesday. Across the Northeast, hot and humid conditions will persist into midweek with heat indices reaching at or above 100 degrees on Tuesday afternoon; heat advisories are in effect from eastern North Carolina around the Mid-Atlantic Coast into southern New England. One or two record highs are possible across portions of the Mid-Atlantic States as temperatures soar well into the 90s Tuesday before a cold front moves into the area and ultimately washes out, returning temperatures back closer to late July norms. Roth Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php