Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 355 PM EDT Thu May 28 2020 Valid 00Z Fri May 29 2020 - 00Z Sun May 31 2020 ...Moisture associated with Bertha could cause additionally locally heavy rain and flash flooding today in portions of the Carolinas and southern Virginia... ...Thunderstorms expected in the eastern half of the U.S., causing heavy rain in the Midwest today and severe weather in the Mid-Atlantic/Northeast Friday... ...Record-breaking heat continues in the West... The remnants of Bertha have reached the eastern Great Lakes and an increasingly humid and warm airmass has engulfed much of the eastern half of the U.S. this afternoon. Showers and thunderstorms should continue this evening over portions of the Southeast and Mid-Atlantic. A Slight Risk of excessive rainfall is in place in the eastern Carolinas as heavy thunderstorms develop and track over the region. Scattered showers and thunderstorms are forecast once again today across the central and eastern U.S. underneath a persistent upper-level low. Strong to severe thunderstorms are most likely over parts of southern Texas and the central Gulf states, where Slight Risks of severe weather have been outlined by the Storm Prediction Center. This upper low will finally lift north and interact with the main jet stream on Friday. At the surface, a cold front is forecast to move across the Midwest this evening and provide a focus for rain and thunderstorms; along and ahead of the front, a Slight Risk of excessive rainfall/flash flooding is in place from the Middle Mississippi Valley into the Upper Great Lakes. Then on Friday as the front moves into the Northeast and Mid-Atlantic, there is a Slight Risk for severe weather in these regions as organized convection could form. Locally heavy rainfall and isolated flooding are also possible there. Behind the cold front, the central U.S. should finally dry out Friday into Saturday with the same cooler and drier regime working its way into the Northeast the second half of the weekend. As the Northeast dries out, a Pacific storm system will soak the Pacific Northwest with periods of rain on Saturday. Heat will be persistent in the West, with high temperatures 15 to 25 degrees above average across California, the Great Basin, and the Southwest through Friday. Daily record temperatures are expected in these areas as temperatures exceed 100 degrees in many places. Heat Advisories and Excessive Heat Warnings are widespread across California and the Southwest. The West Coast should start to cool down by Saturday as a potent upper-level low approaches, but hot temperatures will remain over interior parts of the West. Farther east, the warmest temperature anomalies are expected to be found in northern New England this afternoon and on Friday. Cooler than average temperatures are forecast across the Mississippi Valley behind the cold front but warmer temperatures return to the High Plains by the weekend. Mullinax/Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php