Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 359 PM EDT Wed Apr 11 2018 Valid 00Z Thu Apr 12 2018 - 00Z Sat Apr 14 2018 ...Heavy snow possible over parts of the Northern High Plains, Northern Plains, and Upper Great Lakes... ...Heavy snow possible over the Cascades and the Sierras... A deep upper-level trough just off the West Coast will move eastward to the Central Rockies by Friday morning. The energy will develop a deep storm over the Northern/Central Rockies on Thursday morning moving to Central Plains by Friday. A wave along the associated boundary over the Central Plains will move northeastward to Eastern Maine by Friday. The system will produce rain and snow over parts of the Northern Plains/Upper Mississippi Valley on Wednesday evening with the rain moving to the Lower Great Lakes by Thursday evening as the area of snow moves into Ontario. Overnight Thursday, the rain moves into parts of Northern New England. In addition overnight Wednesday, showers and thunderstorms will develop over parts of Southern Wisconsin and Northern Illinois moving into parts of the Great Lakes/Ohio Valley by Thursday morning. The showers and thunderstorms will end over the Great Lakes/Ohio Valley by Thursday afternoon. Meanwhile, as the upper-level trough moves onshore, rain and higher elevation snow will develop over parts of the Pacific Northwest/Northern California and snow with lower elevation rain over parts of the Northern Rockies on Wednesday evening. Overnight Wednesday, the snow levels lower as the upper-level trough moves farther inland. By Thursday morning, coastal rain and higher elevation snow will move into parts of Central California. Snow and lower elevation rain will move into parts of the Northern High Plains/Northern Plains by Thursday evening. Overnight Thursday, snow will expand eastward into parts of the Upper Mississippi Valley/Upper Great Lakes and into parts of the Central/Southern Rockies by Friday morning. Showers and thunderstorms will also develop over parts of the Central Plains eastward to parts of the Great Lakes/Ohio Valley overnight Thursday with showers and thunderstorms starting over parts of the Southern Plains by Friday morning. Additionally, coastal rain and higher elevation snow will continue over parts of the Pacific Northwest through Friday, too. Elsewhere, upper-level energy over the Northeast on Wednesday evening will move into the Canadian Maritimes by late Thursday morning. The energy will produce rain and snow over parts of the Northeast ending by Thursday afternoon. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php