Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 334 PM EST Mon Feb 24 2014 Valid 00Z Tue Feb 25 2014 - 00Z Thu Feb 27 2014 ...Another round of Arctic air will hold temperatures below normal across the Eastern two thirds of the Nation... ...Numerous showers and thunderstorms expected along the Gulf Coast states... Strong surface ridging nosing down from Canada and expanding over the Central U.S. will spread another round of Arctic air across the Eastern two thirds of the Nation early this week. The fresh supply of Arctic air should keep temperatures below normal...and portions of the Northern Plains and Upper Midwest could see readings in excess of 20 or 30 degrees below normal. Conditions will generally stay dry within this airmass...but impulses of energy racing through the flow aloft could streak some light snows across the Nation's midsection. Shower and thunderstorm activity along a frontal boundary stalled out in the Gulf of Mexico will become more numerous once the boundary surges northward as a warm front and increasing amounts of moisture get drawn out of the Gulf. The front and associated precipitation should push back offshore on Wednesday...but a surface wave developing along the front could clip the Mid-Atlantic states with light snows before it races out to sea Wednesday evening. An upper ridge building in over the Western U.S. will keep locations west of the Continental Divide precipitation free on Tuesday. However...as the ridge starts to break down toward the end of the forecast period...precipitation from a strong Pacific system approaching the coast should begin moving inland over California. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php