Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Sun Oct 30 2016 Valid 12Z Sun Oct 30 2016 - 12Z Tue Nov 01 2016 ...Heavy rain possible over parts of Northern California and Washington State Cascades... ...Snow possible for parts of the Sierras and Northern Rockies... ...Highs will be 10-20 degrees warmer from the Southern Plains to the Southern Ohio/Tennessee Valleys and Southern Appalachians... Scattered showers and thundestorms will be possible over portions of the Lower Great Lakes, Ohio valley, northern Mid-Atlantic and Northeast through early Monday morning as a cold front slowly pushes south. High pressure will build in behind the front; which will reinforce the cooler air, especially for the northeast. In the wake of the system, light rain will develop over part of the interior Northeast on Monday. A few isolateed areas in Upstate New York and Maine may have a wintry mix or all snow. High pressure is expected to remain over much of the southern states through midweek. Afternoon highs of 10 to 20 degrees warmer than those typical for late October will be possible from Southern Plains to the Southern Ohio/Tennessee Valleys and Southern Appalachians. Onshore flow off the Atlantic Ocean will aid in producing showers and thunderstorms over parts of the southeastern portions of Florida through Monday morning. A deep upper-level low off the West Coast will weaken while moving inland to the Northern Rockies and surrounding High Plains by Monday. Rain will develop over parts of the Pacific Northwest and Northern California as the system continues to track inland and spread into southern California, the Great Basin and the Northern/Central Rockies. Snow levels will lower throughout the day today over the Sierras. The highest elevations is forecast to have snow through Monday. Likewise, snow levels will lower over parts of the Northern Rockies, allowing snow to develop over the highest elevations by tonight. The highest precipitation amounts will likely occur over coastal northwest California/southwest Oregon, the Sierras, Coastal Washington and the Cascades - 1 to 3 inches will be common, with isolated 5+ inches possible. Heavy rainfall in these areas may increase the threat for flash flooding through Wedesday morning. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php