Parlty-mostly sunny and milder with lighter winds Tuesday-Thursday. Increasing clouds and winds Friday. Friday night into Saturday we could see some snow showers. Clearing & cold for Sunday. More cold/weak systems are possible next week.
Short Term Forecast
Mostly sunny skies with a few clouds possible through Thursday as high pressure builds in over CA.
Highs warming into the 30s for the upper elevation and 40s for the lower mountains and lake level. Lighter winds are expected through Thursday.
Friday Night - Saturday System:
The latest model runs are shifting the track of the low for Friday evening into Saturday. The latest runs now show the low tracking south through CA. Some models have it tracking near the coast with very little precip reaching the Sierra, and some have it tracking south right over the Sierra with a bit more moisture.
Either way, it looks fairly moisture starved. We will see increasing winds ahead of the system on Friday with ridgetop gusts up to 50-60+ mph from the southwest, which could affect some upper mountain lift operations at exposed mountains. Increasing clouds as well through the afternoon. Highs are still in the 30s for the upper elevations and 40s at lake level.
Rain & snow could reach the Sierra between 4-10 PM Friday evening, with showers possibly continuing through Saturday into Saturday evening before clearing out. But they should be fairly light and scattered over the 24-36 hour period. Snow levels may start near lake level but should fall pretty quickly.
The latest model runs are all over the place with the precipitation forecasts. Some show barely any precip reaching the crest and dry to the east side of the lake with others wetter on the east side than the west with the low tracking over the Sierra and easterly upslope flow developing Saturday.
Snow levels could drop below 4000 ft. Friday night and then sit around 4000-4500 ft. Saturday before dropping below 4000 ft. again Saturday evening. We'll have to keep watching the trends with this system over the next few days. Here is my initial snowfall forecast taking an average of the latest model runs.
Of note is that if the low spins down along the Sierra and into southern NV Saturday, we could see gusty northeast winds set up for Saturday, with ridgetop gusts up to 50-60+ mph. That could affect some exposed upper mountain lifts again.
For Sunday we clear out with colder temperatures behind the storm. Partly to mostly sunny skies and highs into the 30s with lighter winds expected.
High pressure could build in through Monday the 13th with mostly sunny skies and highs warming into the 40s at lake level.
The long-range models show the next cold trough digging south into CA by the 14th with another weak system possible. We could see snow showers return next Tuesday into Wednesday the 15th, along with colder air.
The trough may not stick as the long-range models had suggested previously. We could see it shift east later next week with another break in the storms for a couple of days.
They do show more persistent troughing developing by the 18th into the last week of February. But there are still differences in the position of the ridge off the coast and the trough over the West. The European ensemble mean model sets up a pattern where California is between the ridge off of the cast and the trough to the east.
That could allow some weak systems to drop into the west side of the trough from the north, but overall it keeps us in a below-average precipitation pattern through the 22nd.
The GFS ensemble mean model is showing the ridge farther northwest in the northeast Pacific up near the Aleutians, and the trough centered farther west over the Great Basin.
That would allow storms dropping into the west side of the trough to track over the ocean picking up more moisture, with wetter storms possibly for CA. The GFS model shows above-average precipitation for the northern Sierra for the period of the 18th-22nd.
We'll have to keep watching the trends to see how the pattern may set up. Cool and dry with weak systems at times, or colder and wetter with some decent storms? We'll see...