Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 246 AM EST Sat Feb 13 2016 Valid 12Z Sat Feb 13 2016 - 12Z Mon Feb 15 2016 ...The coldest air mass of the season expected to impact Eastern U.S. this weekend... ...Mild and dry weather expected for the western states... The large-scale weather pattern over the continental U.S. through Sunday 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 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 the weekend. An eddy of the polar vortex over Quebec, along with a reinforcing cold front, is expected to bring the coldest weather of this winter season from the Great Lakes to New England. Wind chill warnings and lake effect snow warnings are in effect for these areas, with wind chill readings dropping below -30 degrees by Saturday night. Actual temperatures will also 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. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php