A stalled front will promote periods of showers and thunderstorms along the Gulf Coast...
Wintry precipitation is possible across the higher elevations of CO
The upper pattern opening up the first full of day of Autumn will consist
of an exiting closed low across upper New England while a trof should remain a mainstay feature over the western states.
As the upper low migrates from the interior Northeast toward Nova Scotia, a surface/upper ridge will build from the west bringing tranquil conditions to most areas east of the Mississippi River through early next week.
A rather significant cold front has worked its way into the coastal
Atlantic carrying much of the associated rainfall offshore of the Eastern Seaboard. Exceptions to this rule are across Upper New England where the associated upper low will be slow to move out of the lower 48.
Further, the frontal zone should remain nearly stalled along the immediate Gulf Coast where showers and thunderstorms will remain possible the next couple of days.
Given the position of the boundary and best moisture content, it appears the heaviest rainfall should be right along the coastline or just offshore.
Across the Western U.S., an upper trof will be a persistent feature during the next few days. The lead system is currently working its way toward the Four Corners region with gradual intensification over the Southern/Central High Plains on Monday morning.
Widespread precipitation is forecast to develop with this system including some higher elevation snowfall over the Colorado Rockies early Monday. The latest forecast from the WPC winter weather desk advertises around 2 to 4 inches of snowfall.
Looking upstream, an expansive upper trof over the Northeastern Pacific and Western Canada will continue to steer a series of impulses toward the Pacific Northwest coast. Enhanced moisture content working in accordance with this energy will bring unsettled weather to areas of the Northwestern states through mid-week. The activity should focus along the coastal regions along with the local mountain ranges given the upslope flow in place.