Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 341 PM EST Wed Dec 02 2015 Valid 00Z Thu Dec 03 2015 - 00Z Sat Dec 05 2015 ...Pacific storm system to bring heavy snow and possible freezing rain to the higher elevations of the northwestern U.S... ...Heavy snow possible for portions of northern Maine... ...Slow-moving frontal boundary expected to bring heavy rain to portions of South Florida... A Pacific frontal system will move onshore in the northwestern U.S. tonight. Ahead of this system, a plume of moisture from the Pacific Ocean will stream into the Northwest, with rain and high elevation snows developing this evening. Rain and snow will continue through Thursday as a wave of low pressure develops along the frontal boundary, which will reach the coast late Thursday afternoon. The cold front will move into the Intermountain states Thursday night, which will cause mountain snow and valley rain to increase across this region. Heavy snow is expected for the Cascades in association with this system, with 1 to 2 feet of snow possible. Additionally, freezing rain amounts of a tenth to a quarter inch are possible in passes and areas prone to cold easterly winds. Farther south in the Sierra Range, 4 to 15 inches of snow is forecast. As the system moves into the northern Intermountain states late Thursday into Friday, snowfall amounts of 4 to 8 inches are possible. Late on Friday, moisture from another Pacific storm system will begin to reach the coast, with showers once again increasing across coastal Washington and Oregon. A low pressure system will bring rain to much of the East Coast this evening. The surface low will move to the New England coastline tonight as colder air spreads into the Northeast on the northwestern side of the system. This will cause rain to mix with or change to snow from portions of the central Appalachians into interior New England. Snow will continue to mix with rain on Thursday across interior portions of the Northeast. Thursday afternoon, the surface low offshore will strengthen as it is invigorated by an approaching upper-level disturbance. At this time, precipitation is expected to change to all snow across northern New England. Heavy snow will be possible at times, with 5 to 10 inches of snow possible for northern portions of Maine. Snow will wind down across northern New England Friday morning as the low pressure system moves into the Canadian Maritimes. The trailing cold front associated with the low pressure system across the Northeast will cross the Florida Peninsula tonight, and will move into South Florida on Thursday. Numerous showers and thunderstorms are expected in association with the front. The frontal boundary will stall on Friday in the vicinity of the Florida Keys, keeping showers and thunderstorms in the picture for much of South Florida. Impressive moisture flowing into this system will result in the potential for heavy rainfall. 2 to 4 inches of rain, with locally higher amounts, are possible across South Florida through Friday. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php