Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 AM EDT Sun May 09 2021 Valid 12Z Sun May 09 2021 - 12Z Tue May 11 2021 ...Severe weather and rainfall potentially causing flash flooding are forecast for the southeastern quadrant of the country... ...Late-season snowfall is likely across the Northern/Central Rockies and High Plains with much colder than average temperatures... ...Warm and dry conditions will cause fire danger in the southwestern U.S. and California... A low pressure system is forecast to move eastward across the Ohio Valley and Mid-Atlantic through Monday, while pushing a cold front slowly southward across the Southern Plains to Southeast. Moisture flowing into the front's vicinity will lead to widespread rain and thunderstorms across those areas. Today and tonight, severe weather is expected from the Southern Plains to the Lower Mississippi and Tennessee Valleys, and an Enhanced Risk of severe thunderstorms is in place from the Storm Prediction Center for tornado, wind, and very large hail threats. Additionally, heavy rainfall could cause scattered flash floods in those regions. Rainfall of over an inch is also possible farther north across the Ohio Valley into Pennsylvania, with notable rain into the Northeast. Then on Monday, storms should focus a bit farther south as the front sinks southward. South-central Texas is most likely to receive severe weather with a Slight Risk in place, but the Gulf Coast states could also see locally strong storms as well as isolated flash floods, while in and around North Carolina should also watch for some strong storms on Monday. In the northern half of the U.S. underneath broad upper-level troughing, much below normal temperatures are likely today and Monday, and these chilly temperatures for May should shift into portions of the Southern Plains and Tennessee Valley on Monday behind the potent cold front. The cold temperatures will support snow across the Northern and Central Rockies, with over a foot possible in some of the highest elevations. Snow is even falling in lower elevations of the Northern Plains, which should continue through this morning. Furthermore, Freeze Warnings and Frost Advisories are in effect this morning for portions of the Snake River Valley in Idaho and parts of the Great Lakes region and Northern Appalachians. Meanwhile, farther south, temperatures will remain hot in South Texas, where temperatures over 100 degrees are expected. California is forecast to be a warm spot as well, with temperatures around 10 degrees above average over the next couple of days. Warm and dry conditions for the southwestern tier of the U.S. has once again led to Elevated to Critical Risks of fire weather for interior portions of California and into the Southwest, Southern Rockies, and Southern High Plains today and Monday. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php