Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Tue May 26 2020 Valid 12Z Tue May 26 2020 - 12Z Thu May 28 2020 ...Thunderstorms with locally heavy rain expected along a front across the Plains and Mississippi Valley, with some severe weather possible... ...Rain spreads into the Carolinas and Virginia Wednesday, which could cause flash flooding... ...Excessive heat builds in the West with record-setting warmth also possible in the Great Lakes region and the interior Northeast... A front is forecast to continue meandering over the Mississippi Valley over the next couple of days, which will help cause rain and thunderstorms over portions of the Plains, Mississippi Valley, and eastward. Locally heavy rainfall is expected, which could cause flooding and flash flooding. Flash Flood Watches are in effect for eastern portions of the Southern/Central Plains and western portions of the Lower/Middle Mississippi Valley, as those areas have been wet recently. Severe weather is expected to focus farther north today, with a Slight Risk in place from the Storm Prediction Center across parts of the Upper Mississippi Valley. Then tomorrow, a Slight Risk of severe weather is outlooked for central Texas. A low pressure system is expected to lift northeastward across Florida today and into South Carolina by Wednesday. Ample tropical moisture streaming into the system will lead to rain and thunderstorms; the heaviest rain should remain offshore today, but the Georgia and South Carolina coasts could receive over an inch of rain, and so could southeastern Florida. Then on Wednesday, rain of 1 to 2 inches with locally higher amounts is forecast for portions of the Carolinas and into western parts of Virginia. A Slight Risk of excessive rainfall/flash flooding is in place for those areas. The upper-level pattern across the country consisting of a ridge in the West, an upper low in the central U.S., and another ridge in the East will remain entrenched over the next couple of days. With this pattern, heat is forecast to persist in California, and widespread record high temperatures should be broken as temperatures of over 100 degrees are forecast in central parts of the state. The potentially record-setting high temperatures should spread eastward into the Central Great Basin and Southwest Wednesday. Excessive Heat Warnings and Heat Advisories are in effect. Meanwhile, the Great Lakes into the interior Northeast can expect high temperatures 10 to 25 degrees above average through Wednesday, as temperatures approach or even exceed 90 degrees, which could also set records. In between, a slow-moving upper-level low should cause below normal temperatures in the Southern Plains for the next few days, and rainfall and cloudiness should keep temperatures more moderate from Southeast Coast into the southern Mid-Atlantic states. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php