Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 307 AM EST Fri Feb 12 2021 Valid 12Z Fri Feb 12 2021 - 12Z Sun Feb 14 2021 ...Steadfast dome of Frigid Arctic air to remain entrenched across the central U.S. and continue expanding south... ...A series of winter storms to result in heavy snow accumulations from the Northwest to the Midwest this weekend... ...Icy conditions possible from the Lower Mississippi Valley to the Mid-Atlantic, showers and thunderstorms in the Southeast... A strong area of high pressure has an icy grip on much of the northern tier of the Lower 48 as an intrusion of Arctic air races south into the Southern Plains. Sub-zero high temperatures are on tap in the northern Rockies and High Plains with some areas seeing morning lows both Friday and Saturday morning between -20 and -30 degrees. Daily temperature departures in the North Central U.S. will range between 30 to 40 degrees below normal. In addition, wind chills remain dangerously cold ranging between -40 and -55 degrees across the Northern Plains. Wind Chill Advisories extend as far south as Oklahoma with wind chills as low as -10 degrees possible through Saturday. The Pacific Northwest will also contend with bitterly cold temperatures as some locations challenge daily record cold max temperatures today. In fact, much of the central U.S. from the Dakotas to Texas could witness many broken daily record low max temperatures through the upcoming weekend. The expansive dome of sub-freezing temperatures across the northern tier of the country has laid the foundation for winter storms to wreak havoc from coast-to-coast not only going into this weekend, but also into next week. Today, periods of snow will blanket portions of the Northwest, the Intermountain West, and Midwest. The heaviest snowfall is anticipated in the Cascades, Tetons, and Colorado Rockies with accumulations over a foot possible. While lesser totals would occurs in parts of the Northwest and central Plains, totals of 3 to 6 inches could lead to hazardous travel conditions. This has resulted in the issuance of Winter Weather Advisories and Winter Storm Warnings in these areas. By Saturday, a Pacific storm system slamming into the Pacific Northwest generates heavy snow and ice accumulations from Portland to Seattle. Pacific moisture out ahead of the storm system reaches the Sierra Nevada, Great Basin, and Intermountain West where periods of heavy mountain snow are likely. Hazardous travel conditions by both ground and air are expected in these areas into the upcoming weekend. In the East, a quasi-stationary front with waves of low pressure along them produces areas of showers along the Gulf Coast and in the Southeast. Farther north, precipitation is forecast to fall in the form snow or a wintry mix over parts of the Mid-Atlantic. Light ice accumulations in parts of the Lower Mississippi Valley and the Piedmont of northern North Carolina and southern Virginia could lead to slick travel conditions this morning. By Saturday, a more consolidated area of low pressure in the Gulf of Mexico directs its rich moisture source northeast towards the Mid-Atlantic. In the warm sector, scattered showers and thunderstorms will engulf much of the Southeast. A few thunderstorms could be severe at times over northern Florida. As the precipitation shield overruns sub-freezing air at the surface in the northern Mid-Atlantic, a wintry mix of snow/sleet/freezing rain will make for potentially treacherous travel conditions Saturday afternoon. Ice accumulations on the order of a tenth to as much as a quarter inch of ice are possible through Saturday evening. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php