Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 453 AM EDT Sun May 19 2019 Valid 12Z Sun May 19 2019 - 12Z Tue May 21 2019 ...Severe thunderstorms and some flash flooding will be possible today from the lower Mississippi Valley to the upper Great Lakes region... ...Additional threats for severe weather today from central New York into the northern Mid-Atlantic region as well as the Texas Panhandle... ...A significant severe weather and flash flood event will be possible across parts of the southern and central Plains on Monday/Monday night... ...Much cooler than average temperatures will continue for much of the Western U.S. and Northern Plains with heavy mountain snow for the central Rockies... A stormy pattern will continue across the lower 48 today with the focus translating eastward into lower Michigan, extending southward into the lower Mississippi Valley. The trigger for potential severe storms will be ahead of a cold front tracking eastward toward the Mississippi River with upper level support favoring the lower Ohio Valley northward into lower Michigan where the Storm Prediction Center has a Slight Risk of severe storms today. Additional threats for severe weather will exist from central/western New York into the northern Mid-Atlantic region with thunderstorms likely developing during the early to mid-afternoon as a warm front moves northeastward allowing summer-like temperatures and humidity to move into New York and the Mid-Atlantic states. Meanwhile, the southern and central Plains are expected to see another round of severe storms and flash flooding on Monday/Monday night ahead of a potent upper level system crossing the western U.S. There is potential for a significant outbreak of severe storms from the Texas Panhandle into western Oklahoma where the Storm Prediction Center has a Moderate Risk of severe storms for Monday. Some of these same locations, as well as a large section of Kansas are included in a Moderate Risk of flash flooding. The central and southern Plains may see multiple rounds of severe storms and heavy rain with forecasts for 3-6 inches of rain across a broad section of Kansas and Oklahoma with locally higher totals possible through Monday night. To the north and west of the low pressure track and active frontal zone, temperatures will remain cooler than average from the West into much of the Northern Plains and Upper Midwest. High temperatures will be significantly below average, over 30 degrees in some areas, in the northern Plains both today and Monday. As the surface low strengthens and tracks east Monday night, heavy snow is expected to develop across the higher elevations of Wyoming into Colorado with minor accumulations possible into the lower elevations of eastern Wyoming. Otto Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php