Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 242 PM EST Sat Jan 19 2019 Valid 00Z Sun Jan 20 2019 - 00Z Tue Jan 22 2019 ...Major winter storm expected to move rapidly across the Ohio/Tennessee Valleys into the Northeast producing heavy snow, heavy rain, and rain/freezing rain... ...Severe weather and flash flooding are possible in the Central/Eastern Gulf Coast... ...Heavy rain possible for parts of Northern California, with heavy snow possible over the Sierras and parts of the Northern Rockies... ...Heavy lake effect snow possible over parts of the Upper Peninsula of Michigan... A strong storm over the Ohio/Tennessee Valleys will move northeastward to the Gulf of Maine by Sunday evening. The storm will produce a swath of heavy snow from parts of the Ohio Valley northeastward into the Northeast with very heavy snow from New York State into Northern Maine through Sunday afternoon. Light snow will continue over Upstate New York to Northern Maine through Monday. Showers and thunderstorms will develop along and ahead of the associated front over the Eastern Gulf Coast into the Southeast that will move off the Southeast Coast by Sunday morning. Rain will also develop over parts of the Southern/Central Appalachians into the Mid-Atlantic and parts of the Southeast that will move off the Mid-Atlantic Coast by Sunday afternoon. Rain will move into Southern New England overnight Saturday moving off the Maine Coast by Sunday evening. Between the rain and snow, a swath of rain/freezing rain will develop over parts of the Ohio Valley into the Northern Mid-Atlantic ending over the Ohio Valley overnight Saturday. Overnight Saturday the area of rain/freezing rain will move northward into parts of New England into Northern Appalachians. The rain/freezing rain will end over New England overnight Sunday. In the wake of the storm, lake effect snow will develop downwind from the Great Lakes through Monday. Heavy lake effect snow will develop over parts of the Upper Peninsula of Michigan through late Sunday night. Meanwhile, a deep upper-level trough over the Eastern Pacific will move onshore over the West Coast on Sunday morning and to parts of the Great Basin/Southern California by Monday. A broad area of moisture will flow into California through Sunday evening. The system will produce rain and higher elevation snow over parts of the Pacific Northwest and snow over the Northern Rockies with rain over Northern California. Overnight Saturday snow will begin to develop over parts of the Southern Cascades. As the trough moves inland, snow will develop over parts of Northern California on Sunday with the snow expanding into the Sierras overnight Sunday as rain moves into parts of Central California. Overnight Sunday, snow will move into parts of the Great Basin. In addition, snow will develop over parts of the Northern Plains overnight Saturday that will end by Sunday evening. Overnight Sunday, snow will redevelop over the Northern Plains into Monday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php