FXUS01 KWBC 180830 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Mon May 18 2026 Valid 12Z Mon May 18 2026 - 12Z Wed May 20 2026 ...Another day of active severe weather and flash flood threat across the east-central U.S. before shifting south into the southern Plains late Tuesday... ...Extreme fire weather concerns across the southern High Plains today... ...Heavy wet snow blankets the higher elevations of Wyoming, the Front Range, and the Wasatch before tapering off tonight... ...An early-season heatwave will challenge temperature records across the eastern U.S.... A rather deep upper-level trough digging into the western U.S. will continue to eject energetic waves out of the Rockies and interact with a stationary front across the midsection of the country. Meanwhile, a Bermuda High will remain anchored across the western Atlantic. This weather pattern will bring another day of active severe weather across the east-central Plains as heavy mountain snow blankets the higher elevations of the northern Rockies, while heat continues to build across the eastern U.S. The greatest threat of severe weather extending from northern Kansas to southern Minnesota early this morning is expected to enter a relative lull during the day. By this evening, the main upper trough is forecast to eject out of the Rockies to trigger a final round of severe weather and heavy downpours across the central Plains to the upper Midwest. The Storm Prediction Center has issued a Moderate Risk of severe thunderstorms from eastern Kansas to southeastern Nebraska through tonight. The Weather Prediction Center highlights a slight risk of flash flooding from east-central Plains to the Midwest with a moderate risk across central Missouri. The main upper trough will finally kick the sluggish system farther south and east on Tuesday, bringing showers and thunderstorms across the Great Lakes with gusty winds. Showers and thunderstorms will extend into the Ohio Valley and the Mid-South Tuesday into Wednesday morning. Stronger thunderstorms appear most likely across eastern half of Texas to the lower Mississippi Valley later on Tuesday into Wednesday morning. Meanwhile, late-season heavy snow is in progress across the higher elevations of Wyoming, the Front Range, and the Wasatch as the main upper trough moves across the region. Strong westerly winds down the slopes of the southern Rockies will meet with dry grounds and low relative humidity to maintain extreme fire weather danger for the southern High Plains today before a cold front brings much cooler air from the north on Tuesday. As the main upper trough ejects into the Plains, the mountain snow is forecast to taper off this evening. Meanwhile, high temperatures will once again top 100 degrees at the hottest locations over the Texas Panhandle today before much cooler air arrives tonight. As snow and severe weather is in full swing across the Rockies into the Plains, the eastern U.S. is entering an early-season heatwave. A Bermuda High will remain anchored over the western Atlantic as a long fetch of warm southerly flow across the eastern half of the country will be warmed further by the strong May sun. High temperatures reaching into the mid-90s will challenge temperature records across the east-central U.S. including the Mid-Atlantic this afternoon, spreading into New England by Tuesday. HeatRisk is forecast to reach major level on Tuesday for major cities across the Mid-Atlantic to New England. Meanwhile, Frost and Freeze related Advisories/Warnings are in place across portions of the northern to central High Plains through Tuesday morning behind the late-season snowfall where Winter Storm Warnings and Winter Weather Advisories are in effect for much of Wyoming into Utah and northern Colorado. Kong Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$