Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 353 PM EST Tue Feb 04 2014 Valid 00Z Wed Feb 05 2014 - 00Z Fri Feb 07 2014 ...A winter storm moving across the Midwest eastward through the Northeast will be followed by another plunge of Arctic air into the center of the country... ...Heavy rain can lead to flash flooding over the Tennessee Valley ahead of a cold front... Another winter storm is shaping up in the center of the nation and will spread eastward into the Northeast during the short-range forecast period. An upper-level trough moving off the Rockies is inducing the formation of a surface low pressure system near the Texas Gulf coast. A swath of snow is already in place over the central Plains ahead of an upper-level shortwave. This area of snow will move eastward in sync with the surface low, which is expected to intensify and move northeastward across the Appalachians on Wednesday. The low is expected to pull somewhat milder air up from the Southeast and the nearby Atlantic, resulting in snow changing to freezing rain and sleet in central Appalachians where significant icing can be expected. Southern New England coast should see snow changing to all rain on Wednesday before ending. However, farther north in the cold air, areas from the lower Great Lakes eastward through central New England should see a foot or more of snow before the system moves out to sea by Wednesday night. In addition to the wintry weather, the low pressure system is also expected to spread heavy rain eastward ahead of a cold front which can lead to flash flooding over the Tennessee Valley tonight into Wednesday. Behind this winter storm, another surge of frigid air from the Arctic is forecast to arrive. Temperatures are expected to drop to more than 40 degrees below normal in the High Plains by the latter half of this week. The southwestern U.S. will be the only area of the country spared from this Arctic blast. Nevertheless, light snow and snow showers are expected along the Arctic boundary from northern California eastward into the central Rockies by early on Thursday. Showers should also begin to move into California on Thursday ahead of a Pacific system. Meanwhile, moisture from the Gulf of Mexico is expected to return to the western Gulf coast early on Thursday, bringing in scattered rain showers into the region. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php