Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 241 AM EST Sun Feb 04 2018 Valid 12Z Sun Feb 04 2018 - 12Z Tue Feb 06 2018 ...Accumulating snow is expected across portions of the central Appalachians, Great Lakes and Northeast for Sunday... ...Unsettled weather will continue for a couple more days over portions of the Pacific Northwest and down across the northern and central Rockies... ...Much above normal temperatures and dry weather will continue through early next week across much of the Great Basin and Southwest U.S... Sufficient cold air is expected to be in place today across the Great Lakes, central Appalachians and Northeast for some accumulating snowfall as a storm system exiting the Midwest quickly lifts across the lower Great Lakes region and portions of the Northeast. The heaviest snowfall will be over interior sections of New York and northern New England where locally over 6 inches of new snowfall can be expected. Farther south over the Mid-Atlantic region, generally a cold rain is expected, however there will be sufficient cold air in place along and east of the spine of the central and southern Appalachians, including the Blue Ridge, for a stripe of freezing rain. This will drive concerns for accumulating ice west of the I-95 corridor for at least a period of time today before the temperatures warm up to above freezing. Meanwhile, farther down to the south, more widespread and heavier rain is expected with a focus from the Tennessee Valley to the Gulf Coast states and including interior areas of the Southeast as a separate area of low pressure impacts this region and draws a more substantial axis of moisture north in off the Gulf of Mexico. All of the unsettled weather impacting the Southern and Eastern U.S. today will begin to taper overnight and through early Monday as a cold front sweeps across the Eastern Seaboard and the Gulf Coast states. This will allow a surge of notably colder and drier air to return to the region, with temperatures generally below normal at least on Monday before then moderating to near normal by Tuesday. Across the West, there will be still a period of unsettled weather continuing today through Monday for areas of the Pacific Northwest and also extending down across the central and northern Rockies as a series of weak Pacific impulses impact the region. Conditions should begin to dry out somewhat by Tuesday, but not before coastal areas of Washington see some additional heavy rain and more concerns for river flooding. Farther inland over the higher terrain, the concern will be heavy accumulating snowfall. Areas of the Washington Cascades, and especially the interior ranges of the northern Rockies including the Bitterroots, Sawtooth and Tetons will see as much as additional 1 to 2 feet of snow through Monday. The influx of Pacific moisture and energy will also overrun an arctic front banked up across the eastern slopes of the Continental Divide for heavy snow to spread out across the northern High Plains with most of the impact on central and western Montana and adjacent areas of northern Wyoming. The remainder of the Intermountain West will be generally very mild and dry with temperatures especially over the Great Basin and parts of the Southwest as much as 10 to 20 degrees above normal. Some record warm high temperatures will be possible locally. Areas east of the spine of the central and northern Rockies and especially across the northern Plains and upper Midwest will be seeing the opposite conditions when it comes to temperatures as these areas will see multiple reinforcing shots of arctic air spilling south from Canada over the next couple of days which will drive temperatures as much as 10 to 20 degrees below normal. Daytime temperatures here will struggle to get out of the single digits and overnight lows are expected to be as much as 20 degrees below zero for some areas. These temperatures coupled with the wind will result in dangerously cold windchill values as a result. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php