Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 310 PM EST Mon Jan 22 2018 Valid 00Z Tue Jan 23 2018 - 00Z Thu Jan 25 2018 ...Heavy snow and rain over parts of Maine... ...Heavy snow over the Cascades, Shasta, and Northern Rockies... ...Rain/freezing rain possible over parts of Northern New England into parts of the Upper Great Lakes... ...Heavy rain possible over the Pacific Northwest... A storm over parts of the Upper/Middle Mississippi Valley will move northeastward to Southeastern Canada by Wednesday. The system will produce snow over parts of the Central Plains and Middle/Upper Mississippi Valley into the Upper Great Lakes and over Northern New England that will end over the Central Plains early Tuesday morning. The snow will briefly end over Northern Maine on Tuesday afternoon returning overnight Tuesday into Wednesday. Also on Tuesday afternoon, snow will start over parts of the Ohio Valley and the higher elevations of the Central Appalachians as well as parts of the Northern Mid-Atlantic by Tuesday evening. Additionally, the snow will wind down over parts of the Upper Great Lakes by Tuesday evening while changing over to all snow over the Ohio Valley. By Wednesday morning, snow will extend from parts of the Northeast into parts of the Eastern Ohio Valley and Central Appalachians. Rain will also develop over parts of the Middle Mississippi Valley/Great Lakes into New England that will continue over parts of the Great Lakes/Ohio Valley into the Northeast through Tuesday morning. The rain over the Southern Ohio Valley will change over to snow by Tuesday evening. The rain will also move off the New England Coast overnight Tuesday. In the transition zone between the rain and snow, bands of rain/freezing rain will develop over parts of the Great Lakes into New England that will end over the Great Lakes by Tuesday afternoon and New England overnight Tuesday. Furthermore, showers and thunderstorms will develop along and ahead of the associated front from parts of the Ohio Valley Southward to the Eastern Gulf Coast by Monday evening that will move eastward to the Mid-Atlantic southward to the Southeast by Tuesday morning. The showers and thunderstorms will move off the Eastern Seaboard by Tuesday evening. Meanwhile, upper-level energy over the Northern Rockies will move eastward to the Northern/Central Plains by Tuesday evening. The energy will aid in producing snow over parts of Northern Intermountain Region/Northern Rockies that will slowly dissipate by Tuesday morning. A deep upper-level trough over the Northern Pacific will move eastward to the Pacific Northwest and Northern California Coast by Wednesday morning. A plume of moisture ahead of the trough will move into parts of the Pacific Northwest by Tuesday morning and into Northern California Tuesday evening into Wednesday. The moisture will aid in producing coastal rain and higher elevation snow over parts of the Pacific Northwest on Tuesday morning that will move inland to the Northern Intermountain Region by Wednesday. Rain and higher elevation snow will also move into parts of Northern California overnight Tuesday into Wednesday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php