From the WPC:
Widespread precipitation will continue across the southwestern corner of the Nation late this week as a deep upper trough edges southeastward towards northern Mexico and low-level winds ahead of the trough pump anomalous Pacific moisture inland. Orographic effects will help produce hefty totals along the upslope side of the terrain…and temperatures should be low enough to support snow accumulations over the higher elevations of the Southern Rockies and Wasatch range.
The widespread precipitation in the Southwest will begin to spread out into the southern and central Plains Friday night into Saturday. Moisture returning from the Gulf of Mexico will fuel moderate to heavy rain and thunderstorms…with any snow initially being confined to the very northern fringe of the precipitation shield. However….as the return flow from the Gulf of Mexico runs into an Arctic airmass dropping through the north central U.S…an axis of moderate to heavy snow is expected to develop across the Midwest. The most significant snow will be near a surface low spinning up over the Middle Mississippi Valley Sunday morning.
Heavy snows and strong winds are expected across Maine Friday night as an abundance of Atlantic moisture wraps inland around a surface low rapidly deepening offshore. The coastal low should steadily lift towards the Canadian Maritimes on Saturday…allowing the snow and winds to diminish over New England.