High Snow Levels Continue for Sunday-Monday

This weekend takes a split weather wise with a bluebird Saturday, at least early on, and a grey day Sunday as light rain (snow) showers commence below (above) 8,000 ft in advance of more significant moisture Sunday night into Monday. The subtropical feed associated with this event will keep snow levels above 8,000 ft until late Sunday. Snow levels will drop to Lake level on Monday as cold fropa passes through. At this time, snow amounts look to be limited due to the wetter/warmer nature of this storm with totals on the order 1-3" below 7,000 ft; 3-6" between 7,000-8000 ft; and 6-12" above 8,000 ft. 

Over time, forecast models continue to show a slower progression for this storm. The momentum slowdown appears hinged to the developing nature of the upper-level flow where the upper-level ridge building in overnight through Saturday positively amplifies across the Great Basin in conjunction with a downstream shortwave that digs back across western Texas / eastern New Mexico (see Figure 1). The net effect of this ridge-trough sequence facilitates the behavior of the upstream trough that we await for Sunday. The orientation (the positive tilt) of the latter then reveals a subtropical fetch along the central California coast Sunday into Monday (see Figure 2).

Figure 1 illustrating the upstream ridge-trough sequence that slows the eastward
progression and sets up the subtropical fetch depicted in Figure 2.

Figure 2 depicting the subtropical fetch (precipitable water) spreading into northern-central California.

Because the models continue to change the progression of this event, a short update will be issued early Sunday incorporating new details. In the meantime, get out early on Saturday and enjoy bluebird conditions.