Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 250 AM EST Sun Feb 14 2016 Valid 12Z Sun Feb 14 2016 - 12Z Tue Feb 16 2016 ...The coldest air mass of the season over the Northeast U.S. through Sunday... ...Wintry weather developing over the southern Appalachians and parts of the Mid-Atlantic region... The large-scale weather pattern over the continental U.S. through Monday will be featured with a large scale ridge over the Intermountain West and a trough over the Eastern U.S. The amplified flow will result in mild and mainly dry weather west of the Rockies, and periods of rain and mountain snow for the Pacific Northwest. Warm weather is forecast to continue for the Desert Southwest and California with little in the way of precipitation. Arctic air will be the big story across the northeastern U.S. through Sunday night. An eddy of the polar vortex over southeastern Canada, along with strong cold air advection, is bringing the coldest weather of this winter season from the Great Lakes to New England. Wind chill warnings and advisories are in effect for these areas, along with some record low temperatures. Actual temperatures will be frigid with highs in the single digits and teens, and subzero lows across much of upstate New York and New England. It will also be quite cold from the Ohio Valley to the Mid-Atlantic region. By Monday, a developing storm system over the Deep South is forecast to track northeastward over the Appalachians and bring a variety of precipitation types to the eastern U.S. Rain is expected over the Gulf Coast states and the southeast Coast, and snow is likely over far inland portions of the Mid-Atlantic region and the interior Northeast. Freezing rain and sleet is also likely just west of the Interstate 95 corridor and including western North Carolina through central Maryland, where winter storm watches are currently in effect. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php