Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 407 PM EDT Mon Oct 18 2021 Valid 00Z Tue Oct 19 2021 - 00Z Thu Oct 21 2021 ...Upper level low to generate accumulating mountain snowfall from the Sierra Nevada to the Intermountain West... ...Elevated Risk of fire weather in the Central-Southern Plains today and tomorrow... ...Below normal temperatures to persist in the West; seasonally cool temperatures along the East and Gulf Coasts to moderate by mid-week; warmest temperatures versus normal in the Upper Midwest & Great Lakes... As a large dome of high pressure keeps a tranquil weather pattern in place across much of the South and East, the western half of the Lower 48 will feature the most active weather to kickoff the work-week. An area of low pressure associated with a potent upper-level low is forecast to continue an eastward track from the northern Great Basin into the heart of the Intermountain West by tonight. As the system progresses east toward the Rockies, snowfall accumulations over a foot are possible in higher elevations through Wednesday morning, particularly over portions of the Wasatch, Wind River, Laramie, Bighorn, and Front ranges. Accordingly, portions of Central Wyoming remain under a Winter Storm Watch (with embedded Winter Storm Warnings), while a Winter Weather Advisory is in effect in Northeast Utah through Tuesday. Meanwhile, lower elevation areas in the Intermountain West can expect benign showers and thunderstorms that will subside by Tuesday night as the system ejects over the Plains. South of the precipitation activity, the passage of a cold front will produce gusty winds across portions of the Desert Southwest and Southern Great Basin, where Wind Advisories are in effect through this evening. The next round of active weather in the West arrives Tuesday afternoon as another Pacific system brings rain and some mountain snow chances to the Pacific Northwest. East of the Rockies, the approach of the strong upper-level low will facilitate lee troughing over the Plains, where dry and breezy conditions support an Elevated Risk of fire weather today and tomorrow over the Central/Southern Plains per the SPC Fire Weather Outlook. Locally, a Red Flag Warning and Fire Weather Watch encompasses Southwest Kansas and Southeast Colorado through tomorrow evening. Temperatures the first half of the week will be coolest versus normal over the western third of the CONUS. Daily temperature departures ranging between 10 to 15 degrees below normal are anticipated today for much of California and Nevada. As the upper trough responsible for the wintry weather in the Rockies moves east on Tuesday, temps will cool to below normal levels as it works in tandem with another cold front pushing south through the Northern Plains. Meanwhile, seasonally cool temperatures will stick around in the Deep South and along the East Coast today. Look for temperatures to gradually warm up along the Gulf and East Coasts, eventually returning to above normal levels by mid-week. Lastly, the regions witnessing the warmest temperatures versus normal will be the Midwest and Great Lakes today and Tuesday. Daytime highs will soar into the 70s with some locations in the central High Plains potentially reaching as high as 80 degrees. Asherman/Mullinax Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php