Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 332 PM EDT Sun Apr 29 2018 Valid 00Z Mon Apr 30 2018 - 00Z Wed May 02 2018 ...Rain and mountain snows continue through Tuesday across the Northwest with some snowfall accumulations possible in the northern Rockies... ...Severe weather chances increasing through Tuesday across the Plains and into the upper Midwest... An expansive upper level system shifting slowly through the West will bring mainly light to moderate rain and mountain snows to much of the Northwest and into the northern Rockies through Tuesday. A gradual cooling trend will continue into the early part of the work week, which should support some modest snowfall accumulations in the highest elevations of the northern Rockies. Return moisture ahead of this system will lead to the development of showers and thunderstorms across the southern Rockies and the adjacent High Plains beginning tonight and through Monday, and shifting eastward into the central Plains and upper Midwest by Tuesday. The Storm Prediction Center has highlighted a marginal to slight risk for severe weather tonight and into Monday from the southern High Plains to the northern Plains. By Tuesday, the severe threat moves south and east into the central Plains and the upper Midwest where a slight to enhanced risk is possible. Ahead of this system, very warm temperatures are expected with afternoon highs as much as 10 to 15 degrees above normal across the central U.S., expanding eastward with time into the Midwest and the upper Great Lakes. The warm, dry, and windy conditions will allow for an elevated to critical fire weather threat across the Four Corners states through Tuesday, as well as farther north across the upper Mississippi Valley on Monday before rain and storms move in on Tuesday. Widespread red flag warnings are in effect across both of these regions. Elsewhere, a lingering surface low over New England will continue to support scattered showers and overnight snow showers to parts of the Northeast and the Central Appalachians. Places across much of the Eastern states will begin the week on the cooler side, but temperatures should quickly rebound to above normal by mid-week. Santorelli Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php