Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 233 PM EST Fri Dec 21 2018 Valid 00Z Sat Dec 22 2018 - 00Z Mon Dec 24 2018 ...Threat of heavy rain continues for New England through tonight... ...Accumulating snow for the central and southern Appalachians through Saturday morning... ...Wet/Snowy pattern continues for the Northwest... A powerful storm system continues to impact the eastern U.S. with anomalously warm temperatures in place from the Mid-Atlantic into southern New England along with gusty winds near the coast and heavy rain. An anomalously moist axis ahead of the system's cold front was responsible for heavy rain and flooding in and around the New York City metropolitan area earlier today but the heavy rain threat going through the night will be farther north and east. An additional 1-2 inches of rain will be possible for portions of New England tonight where flood watches are currently in effect. On the back side of the storm system will be colder air filtering into the Ohio Valley and Northeast allowing a changeover from rain to snow for some of the higher elevations of the central and southern Appalachians where mainly light accumulations are expected through late Saturday morning. Precipitation may end as light snow for portions of the Northeast as well but accumulations, if any, should be very light away from the Appalachians. Temperatures will be significant cooler and much closer to average for the weekend across the East. A weak storm system is expected to bring light rain/snow from the Tennessee Valley into New England (temperature dependent) on Sunday but it will otherwise be very quiet to start the beginning of next week. Across the Pacific Northwest, a frequent succession of systems will affect the region bringing a combination of lower elevation rain and mountain snow to Washington, Oregon and portions of the Interior Northwest. The heaviest precipitation is expected to begin mid-late Saturday ahead of a strong Pacific cyclone with the cold front making landfall overnight. While locally heavy rain will be possible through Sunday, rainfall is expected to be spread out enough over time to not cause flooding concerns. The middle of the nation will be between storm systems with a relatively quiet pattern in place. Any precipitation over the next 2-3 days will be light with temperatures generally above average. Otto Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php