Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 346 AM EDT Sun Mar 19 2017 Valid 12Z Sun Mar 19 2017 - 12Z Tue Mar 21 2017 ...Record warmth over much of the western U.S. expected to spread into the northern and southern Plains... ...Cold temperatures and wintry precipitation today across portions of the Northeast and northern Mid-Atlantic... A mix of rain and snow is currently falling over portions of the Northeast and the interior mid-Atlantic into the western slopes of the central Appalachians and is forecast to continue through the day and into Monday morning. Snow will likely linger from Massachusetts to eastern Maine as the low pressure center deepens offshore and continues to track northward toward the Canadian Maritimes. Cold air filtering in behind the front will drop temperatures well below normal for much of the Eastern Seaboard on Monday before a moderating trend begins on Tuesday. Across the West, a strong cold front will bring lower elevation rain and mountain snow across the Pacific Northwest over the next few days. A portion of the front is expected to become stationary, keeping the rain and snow across northern California, much of Oregon, the Great Basin, Intermountain West, and Northern Rockies today. The northern portion of this system will push through the Northern High Plains and Upper Midwest before sagging into the Central Plains on Monday. Showers and thunderstorms are forecast to initiate along and ahead of the advancing boundary, spanning from the Mid-Mississippi valley to the Great Lakes region by Monday morning then expanding eastward into the Tennessee/Ohio valleys and the Appalachians by late afternoon. Cold air trapped in some of the valleys of the northern Appalachians and northern New England could see resulted in snow or a wintry mix. Onshore flow in conjunction will another Pacific system approaching the West Coast will result in another round of widespread rain with possible higher elevation snow. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php