Weather across America

(NATIONAL) Snow over parts of the Cascades, Great Basin, Northern/Central Rockies and Sierra Nevada Mountains, snow over parts of the Great Lakes and the Northeast, followed by a second round of snow over the Upper Mississippi Valley, and pockets of rain/freezing rain over parts of the Upper Midwest. 

A deep upper-level trough will move onshore over most of the West Coast on Sunday, moving to the Upper Great Lakes to the Southern Rockies by Tuesday. The system produced rain and higher-elevation snow over parts of the Pacific Northwest and most of California on Sunday morning. The snow expands eastward into the Northern Intermountain Region and Great Basin by Sunday evening. 

By Monday morning, the rain and snow will end over most of California while continuing over parts of the Northwest and Northern Intermountain Region/Great Basin, moving into the Northern and Central Rockies. Overnight Monday into Tuesday, rain and higher elevation snow will continue over the Northwest, while scattered snow continues over the Rockies.

Meanwhile, a front over the Upper Midwest overnight Sunday will move into the Northeast and off the Northeast Coast by Monday afternoon. On Sunday, the boundary will produce light snow over parts of the Upper Great Lakes. Overnight Sunday, the snow will move into the Lower Great Lakes and Northern New England, ending by Monday evening.

On Monday, low pressure over the Central Plains will move northward into Southern Canada by Tuesday. Moisture will stream northward over the Mississippi Valley into the Upper Midwest. On Monday afternoon, snow will develop over parts of the Upper Mississippi Valley and the Upper Great Lakes. 

In the meantime, rain will develop over parts of the Central Plains and expand southward into the Middle Mississippi Valley/Southern Plains. Rain will continue to expand along the front from the Southern Plains into the Western Ohio Valley and Great Lakes. Near the rain/snow line, pockets of rain/freezing rain will develop overnight Monday into Tuesday morning. The snow will result in reduced visibility/hazardous driving conditions and ice may cause dangerous road conditions, too.