Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 507 AM EDT Thu Oct 03 2013 Valid 12Z Thu Oct 03 2013 - 12Z Sat Oct 05 2013 ...A storm system evolving over the Central U.S. will carry a threat of accumulating snows...heavy rains...and severe weather... ...Potential tropical system could bring rains into the Central Gulf Coast... ...Hot and humid will remain the story across much of the Eastern U.S.... A vigorous upper trough carving out and closing off over the Western U.S. will set the stage for a high impact event heading into the close of the work week. Initially...the focus will be in the Northern/Central Rockies...where increasing low level easterly/northeasterly flow against the terrain will produce widespread heavy snows not only in the mountain peaks but down in the front range as well. Friday evening...as the energy aloft ejects out into the Plains...a deepening surface cyclone in the lee of the Colorado Rockies will begin its track northeastward towards the Upper Mississippi Valley. Moderate to heavy precipitation is expected to develop to the northwest of the low track...leaving behind a swath of the season's first snowfall accumulations from the high plains of Wyoming into the Western Dakotas. A trailing cold front from the strengthening cyclone will ignite strong to potentially severe storms as it races through the Central Plains Friday night into Saturday...plummeting temperatures in its wake. Meanwhile....an abundance of Gulf moisture getting pulled well north ahead of the system will help fuel scattered showers and thunderstorms along a frontal boundary stretched from the Midwest to the Northern Mid-Atlantic Coast. Multiple waves along the front could lead to some organized areas of convection and moderate to heavy rains. To the south of the boundary...conditions will remain hot and humid across the Eastern U.S.. Across the southern tier of the Nation...all eyes will be on an area of showers and thunderstorms that have the potential to develop into a tropical system as they move into the Gulf of Mexico. Moisture from the potential system could bring moderate to heavy rains into the Central Gulf Coast by the end of the forecast period...but please refer to the National Hurricane Center for the latest information. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php