Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 430 PM EDT Mon Oct 13 2014 Valid 00Z Tue Oct 14 2014 - 00Z Thu Oct 16 2014 ...The severe weather risk moves slowly eastward over the next couple days with a slight risk over the Southeast on Tuesday and a diminishing chance along the East Coast on Wednesday... ...A slow moving storm system will bring an increasing chance for heavy rains especially across the Upper Great Lakes, the lower Mississippi Valley and across the Appalachians... ...A wet onshore flow will also bring some significant rainfall to the Pacific Northwest Coast with 2 to 3 inch amounts possible from northern California to western Washington... A large and slow moving storm system will affect the eastern half of the US thru Thursday. Its main impact will be widespread rainfall, some severe weather with mild temperatures giving way to cooler temperatures but no extremes in temperature are expected during this period. Low pressure will move northeastward across the Mississippi Valley toward the Midwest through Tuesday, while a slow moving cold front moves eastward reaching the East Coast by Wednesday. While the greatest severe weather threat is likely today, there is still the risk of severe thunderstorms, flash flooding and an isolated tornado across the Southeast with lesser chances across the Tennessee and Ohio Valleys on Tuesday. A modest risk will exist along the East Coast on Wednesday but the biggest threat will remain to be rainfall. Heaviest rains of greater than 2 inches are possible across the Upper Midwest, the Southeast and portions of the Appalachians. Cooler weather will follow behind the cold front with some instability showers remaining in the cooler air across the Midwest, Ohio and Tennessee Valleys and Appalachians by Wednesday. An active weather pattern is expected start moving into the Pacific Northwest tonight with subsequent impulses of Pacific moisture coming ashore over the next few days. Rainfall amounts along the immediate coastline could be 3 inches or greater over the next few days from northern California, western Oregon and Washington. Snow levels will start to come down with the Cascades seeing the greatest likelihood of snow during this period. After a frost tonight over Colorado, a significant warming trend is expected over the next few days. Kocin Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php