Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 PM EDT Sun Mar 13 2016 Valid 00Z Mon Mar 14 2016 - 00Z Wed Mar 16 2016 ... Strong to severe thunderstorms, with heavy rain possible today for the lower Mississippi Valley... ...Rain and mountain snow for the West Coast and Intermountain West... Showers and thunderstorms are popping up over portions of the Central and Southern Plains and lower/middle Mississippi Valley this afternoon. The Storm Prediction Center has highlighted portions of the lower Mississippi Valley as having a slight to enhanced risk for severe thunderstorms through Monday morning. Periods of heavy rain will be possible with this convection; which may lead to flash flooding. A slight and moderate risk for excessive rainfall has been issued for portions of the lower Mississippi Valley. River levels will remain quite high across this region as all of the rain water slowly drains away. Scattered to widespread rain is forecast for a majority of the eastern third of the U.S. A low pressure system is lifting north and east from the South as Gulf moisture streams in overheard. At the same time, a frontal system will push south and east across the High Plains into the Upper Midwest/Great Lakes/Ohio Valley area. Rain amounts up to 1 inch will be common over the next few days. Cool and dry conditions are expected through Monday morning before the precipitation begins. Mild weather is also expected from the Mid-Atlantic to the Southeast with afternoon highs in the 60s and 70s, which is above seasonal averages. A series of frontal systems will progress eastward through the West and Intermountain West bringing multiple rounds of rain and mountain snow over the next couple of days. The Cascades and the Sierra Nevadas are forecast to have the highest snow accumulations; where 3-day totals of 1 to 3 feet will be possible at the highest elevations. Windy conditions are expected for coastal areas with wind gusts exceeding 50 mph at times, and wind advisories and high wind watches are in effect. The Sawtooth Range and Salmon River Mountains in Idaho could accumulations nearing 2 ft. Lower elevations/coastal areas from the Olympic peninsula to northern California will have multiple periods of heavier rainfall. The risk for flash flooding will remain elevated for southwest Oregon and portions of northern California through Monday morning. An Excessive Rainfall Outlook is in effect for northern California and southwest Oregon. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php