Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 147 PM EST Sat Dec 19 2015 Valid 00Z Sun Dec 20 2015 - 00Z Tue Dec 22 2015 ...Stormy pattern to continue across the northwest U.S... ...Above normal temperatures to return to much of the East along with increasing precipitation chances... No real change to the large scale pattern affecting the lower 48 states is expected over the next several days as the rather progressive weather pattern dominated by Pacific, rather than Arctic air, will continue. In the west, the next in a series of Pacific frontal systems is forecast to move into the Pacific Northwest Saturday night bringing coastal/valley rains into western Washington, Oregon, and northern California with snows in the higher terrain. This should be a rather quick moving system but could still bring modest snowfall amounts from the Cascades eastward into parts of the northern Intermountain west into Sunday. On its heels, another storm system racing eastward across the Pacific will bring another shot of precipitation along with strong winds into the Pacific Northwest Sunday night with snows increasing once again near and east of the Cascades Sunday night and Monday...which could have an impact on early Holiday travel plans. Over the central and Eastern U.S, after an initial chilly and mostly dry start...a return to above normal temperatures is in store for a good portion of the region as return flow from around large high pressure moving off the East Coast allows warmer Gulf of Mexico air to surge northward east of the Mississippi River by Sunday. This return flow will also help gather some moisture ahead of an advancing Pacific cold front and developing low pressure system that will lift northeastward towards the Great Lakes region by Monday morning. This will support an increase in showers mainly near and especially east of the Mississippi River region Monday into Tuesday morning..with any winter precipitation restricted to Canada and parts of the Western Gt lakes region and even there, amounts should be light. Behind the front...seasonably cooler air will settle southward into the central and southern plains but that too is expected to be rather short lived. Sullivan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php