Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Wed May 27 2020 Valid 00Z Thu May 28 2020 - 00Z Sat May 30 2020 ...Tropical Depression Bertha threatens the Southern Appalachians and Mid-Atlantic with the potential for flooding and gusty winds... ...Widely scattered showers and thunderstorms to dot the eastern half of the Lower 48 the remainder of the work-week... ...Record-breaking heat continues in the West while cooler temperatures return in the Midwest and Great Lakes... After making landfall as a Tropical Storm earlier today, now Tropical Depression Bertha is expected to track northwest escorting tropical moisture northward into the southern Mid-Atlantic. In fact, the southern Appalachians and Shenandoah Valley are most at risk for flooding due to the overly saturated soil from recent heavy rainfall and rainfall rates becoming more intense where orographic lift is maximized. As a result, a Moderate Risk for excessive rainfall is in place in southwest Virginia and far northwest North Carolina tonight. In addition, a Slight Risk for excessive rainfall and a swath of Flash Flood watches extend from southeast West Virginia to the coasts of southern North Carolina and northeast South Carolina. Rainfall amounts could exceed several inches in the southern Appalachians and along the coastline of South Carolina and southern North Carolina. By Thursday morning Bertha's circulation is forecast to end up in eastern West Virginia where it will be wet and anything but wonderful as widespread showers, some heavy at times, drench much of the state. The storm's remnants also usher a tropical air-mass into the Mid-Atlantic with warm and humid conditions surging up the East Coast with spotty showers and storms from the Southeast to southern New England. The tropical air-mass will engulf the Eastern Seaboard Friday but relief in the form of a cold front will provide relief in lower dew points and cooler temperatures by the weekend. Speaking of showers and thunderstorms, there is no shortage of showers and storms this afternoon in the Mississippi Valley thanks to an upper low over the region and an elongated frontal boundary stretching from east Texas to the northern Great Lakes. Severe weather is anticipated in the Lone Star state where central Texas is under an Enhanced Risk for severe weather this evening. A cold front sweeping across the Midwest on Thursday forces the upper low to pick up the pace late Thursday resulting in the severe threat encompassing much of the South. A Slight Risk for excessive rainfall is also in place the western Great Lakes on Thursday as rainfall rates could become heavy. By Friday, the aforementioned cold front's passage will make for a drier Friday across the Midwest while areas of showers and storms develop in the hot and humid air-mass over the Ohio Valley and Northeast. In the West, an upper-level ridge refuses to loosen its grip over the western third of the country through Thursday. High temperatures should be roughly 10 to 20 degrees above average over California, the Southwest, and the Great Basin. More record high max and high minimum temperatures are likely on Thursday and Excessive Heat Warnings and Heat Advisories remain in effect with temperatures surpassing the century mark in some areas. By Friday, the heat becomes increasingly stifling in the Great Basin and Snake River Valley where high temps make a run at the upper 90s. On the flip side, below normal temperatures and more comfortable humidity levels arrive in the Midwest and Great Lakes on Friday. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php