Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 252 PM EST Wed Mar 01 2017 Valid 00Z Thu Mar 02 2017 - 00Z Sat Mar 04 2017 ...Severe storms possible across the Tennessee valley, the Southeast, the Mid-Atlantic and southern New England today... ...Unsettled weather to return to the Pacific Northwest... An expansive line of strong-to-severe thunderstorms continued over the Ohio/Tennessee valley from overnight and has tracked eastward toward the Appalachians this afternoon ahead of the advancing cold front. A broad threat for severe storms continues for the Ohio and Tennessee valleys into the I-95 corridor from New York City down into the Carolinas through tonight. While strong straight line winds are expected to be the main concern, large hail and tornadoes will also be possible along with flash flooding. A tornado watch is in effect from central Alabama to southeast Tennessee/northwest Georgia this afternoon. The flash flood threat will be especially focused along the upper Ohio valley into the north-central Appalachians today. Please refer to the Storm Prediction web page for additional information on the threat of severe storms. Light to locally moderate snow from eastern Wisconsin into northern lower Michigan, where up to 6 inches will be possible, will persist this afternoon before beginning to taper off during the evening and overnight hours. Cooler air will filter in behind the front, which will result in near seasonal average temperatures for much of the country. A secondary surge of cold air into the Northern High Plains will keep the Dakotas and part of Minnesota in the teens and 20s on Thursday. Fairly quiet weather will return to much of the nation once the large storm system exits the U.S. and continues tracking eastward over the Atlantic Ocean. Light snow, possibly mixed with rain on the south side, will streak across portions of the Midwest on Thursday, reaching the northern Mid-Atlantic region Friday morning. Light rain and snow is forecast to continue across portions of the Pacific Northwest through Thursday morning. Another round of precipitation is expected by the weekend as a cold front approached from the North Pacific. Lower elevation rain and mountain snow will overspread western Washington and Oregon. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php