Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 242 AM EST Sun Jan 22 2017 Valid 12Z Sun Jan 22 2017 - 12Z Tue Jan 24 2017 ...Severe thunderstorms possible today with embedded regions of moderate risk over the Southeast... ...Heavy rain possible along the West Coast... ...Heavy snow for the Sierras... ...Heavy rain over portions of the Gulf states and the Southern Appalachians... Widespread rain and thunderstorms is forecast for much of country along and east of the Mississippi valley as two systems lift through the Lower Mississippi valley, the Gulf states, the Tennessee valley, the Southeast and Mid-Atlantic region. Another system located north of the southern systems with track across the Great Lakes region and the Ohio valley. Strong to severe thunderstorms are expected to develop across the Southeast today. The Storm Prediction Center has highlighted this portion of the country having slight to moderate risk for severe thunderstorm development. In addition, heavy rainfall will be possible in this region and may lead to flash flooding. A deep upper-level low will continue to track toward the Pacific Coast over the next couple of days. A plume of moisture streaming into southern California will persist today and wane by Monday. Coastal rain and higher elevation snow over the Pacific Northwest to central California is expected to continue while spread south into southern California and further into the Great Basin and Rockies. Snow and coastal rain will slowly decrease across the Pacific Northwest by Monday morning. Rain and snow will be heavy at times over central/southern California through Monday morning - excessive rainfall is expected through early Tuesday for the central and southern California Coast. Flash flooding may occur during this time. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php