Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 403 PM EST Fri Nov 21 2014 Valid 00Z Sat Nov 22 2014 - 00Z Mon Nov 24 2014 ...A Pacific front is expected to move across the Intermountain West on Saturday and then bring increasing storminess into the central and northern part of the U.S. on Sunday... The short-range forecast period begins with a fine and cool note in the eastern U.S. under the influence of a large dome of high pressure. Return flow from the south has been slowly bringing warm and moist air from the Gulf of Mexico into the southern Plains and has triggered scattered showers and thunderstorms. As the high pressure slides off the mid-Atlantic coast during the weekend, a Pacific front will be moving through the Intermountain West, where widespread mountain snows can be expected. The snow will gradually become more widely scattered in the West as the front moves steadily away into the Plains on Sunday. With the surface front and the associated upper-level trough approaching, more moisture will be pumped into the Deep South where stronger thunderstorms will become possible on Sunday. More widely scattered thunderstorms could develop in the Midwest and will move toward the Ohio Valley. By Sunday night, we should be dealing with a double barrel low pressure system moving into the entire length of the Mississippi Valley. Somewhat colder air will also move into the northern Plains behind the low. Temperatures in the East will continue to warm up from well below normal to near normal by Sunday along with increasing moisture. Meanwhile, rain associated with a warm front should be moving into the Carolinas by Sunday evening. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php