Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 449 AM EDT Fri Oct 02 2015 Valid 12Z Fri Oct 02 2015 - 12Z Sun Oct 04 2015 ...Flash flooding expected over portions of the Southeast and Mid-Atlantic States... ...Rain expected for much of the Intermountain West and Pacific Northwest... A stalled frontal boundary will persist along the East Coast for a few days. A surface low along the front off the Georgia/Florida coast will drift westward over the next couple of days as an upper-level low deepens over the Southeast. The combination of the surface low, frontal boundary, and a plume of moisture streaming westward into the Southeast from Hurricane Joaquin, will result in a period of very heavy rainfall over portions of the Southeast and southern Mid-Atlantic states. Rain fall totals will range significantly along the eastern seaboard. A majority of the area could see 1 to 5 inches by Monday morning, with 5 to 15+ inches possible from Virginia to the South Carolina-Georgia border. The widespread heavy rainfall will result in a significant threat of flash flooding across the Mid-Atlantic and Southeast regions. Hurricane Joaquin is forecast to remain offshore through Monday morning. Please refer to the latest products from the National Hurricane Center for details on the forecast for Hurricane Joaquin. Scattered to numerous showers are forecast for the Intermountain West as a surface cold front moves through the region. An additional upper-level disturbance will move into the Pacific Northwest Friday evening, bringing showers to the Pacific Northwest, which will then spread additional moisture across the northern Intermountain West on Saturday. Rain is forecast to mix with snow at the highest elevations of Wyoming, Idaho, Montana, Utah and Colorado. The wintry mix will change over to mostly snow for western Montana and Wyoming by Sunday morning, with accumulations of 1 to 4 inches possible. Scattered showers and thunderstorms will also be possible through Saturday across the Plains, as a weakening frontal boundary lingers east of the Rockies, and moisture flowing into the region interacts with this front as well as upper-level disturbances passing through the region. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php