Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Sun May 19 2019 Valid 00Z Mon May 20 2019 - 00Z Wed May 22 2019 ...A significant severe weather and flash flood event is possible on Monday across parts of the Southern and Central Plains... ...Well below normal temperatures likely to persist across much of the western and northern parts of the nation Monday and Tuesday... ...Widespread record warm lows possible Monday morning in the Northeast, with above normal temperatures expanding across the Southeast... The big highlight in the short range period is with what could be a potentially significant severe weather and flash flood event across parts of the Southern and Central Plains ahead of a strong upper level system ejecting into the Rockies and High Plains on Monday. The biggest threat for severe weather will be from northwest Texas to southern Kansas, where SPC is advertising an enhanced to moderate risk for large hail, damaging wind gusts, and/or strong tornadoes. Widespread heavy rainfall is also expected to accompany this system, with WPC highlighting parts of the Texas Panhandle to central/eastern Kansas within a moderate risk for excessive rainfall/flash flooding where as much as 3 to 6 inches of rain is in the forecast. The threat shifts north and eastward on Tuesday, with SPC showing a slight risk for severe weather from eastern parts of the Plains to the middle Mississippi Valley, and WPC having parts of the northern/central Plains to the middle Mississippi Valley in a slight risk for flash flooding. Meanwhile to the north and west of the low pressure track and active frontal zone, temperatures will remain well below normal across the interior West and into the Northern Plains and Upper Midwest Monday and Tuesday. Particularly across parts of the northern/central High Plains, temperatures could be 25 to 30+ degrees below normal, with record or near record cold daytime highs possible. Frost advisories and freeze warnings are also in effect for parts of the Dakotas and western Minnesota tonight and into Monday morning. Across the higher elevations of Wyoming and Colorado, heavy snowfall is likely, with minor accumulations also possible in the lower elevations of eastern Wyoming. And along the West Coast, a deep surface low approaching the coast Monday night into Tuesday could bring a round of heavy precipitation to parts of northern California and southwest Oregon. In the Eastern U.S., a cold front will bring showers and thunderstorms to parts of the region through Monday, with locally heavy rainfall possible and a slight risk of severe weather across parts of New England. Ahead of the boundary, temperatures will be very warm, with record warm lows possible Monday morning from the Mid-Atlantic into the Northeast. Temperatures throughout the day on Monday should moderate to near normal following the passage of the cold front. Across the Southeast, a building upper level ridge will keep temperatures seasonably warm with highs near or above 90 degrees for many. Santorelli Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php