Wednesday – Thursday:
The latest model runs still show rain & high elevation snow showers moving in over the mountain Wednesday morning. Snow levels start up around 7300-7800 ft. but could dip close to the base by the end of the day, especially under any heavier precipitation. Strong winds through Thursday with ridgetop gusts up to 80-100+ mph. Highs into the 40s for the lower elevations and 30s for the higher elevations.
The rain is expected to continue Wednesday night into Thursday with snow levels rising Wednesday night. Up to around 9000-10,000 ft. by early Thursday morning. That will turn snow to rain on most mountain surfaces. The snow levels could sit in that range through Thursday.
Most of the snow is expected for the higher elevations through Wed evening, with mostly rain expected below 9000-9500 ft. Thursday. Any snow that falls will have low snow ratios and will be wet. We could see a little wet snow to the base, 1-6 inches near mid-mountain, and 7-13 inches up top before the change to rain.
Friday – Saturday:
The steadier precipitation is forecast to move back in through the day on Friday, with heavy rain & high elevation snow possible by Friday afternoon. The snow levels slowly start to drop, down to around 7000-8000 ft. by the end of the day, and then dropping near to just below the base by Saturday morning. The strong winds continue with highs in the 40s for the lower elevations and 30s up top.
There will be a boom/bust time period for snowfall between 7000-8000 ft. depending on the snow levels. Snow showers could linger into Saturday afternoon with snow levels hovering near to just below the base. Highs drop into the 30s for the lower elevations and 20s for the higher elevations. Gusty winds but possibly diminishing some through Saturday afternoon.
This is another tricky period to be forecasting snowfall totals with the exact timing of the colder air moving in vs the heaviest precipitation moving through being unknown. The snow ratios will start to increase Friday night into Saturday with the higher elevations snowfall becomes less wet, but not powdery. We could see 2-day totals around 3-7 inches at the base, 13-18 inches near mid-mountain, & 19-25 inches up top.
Sunday – Monday:
The low-pressure center spinning off of the West Coast is forecast to tap into some additional moisture before moving through Sunday into Sunday night. As it taps into some subtropical moisture it is expected to draw in slightly warmer air on Sunday, with snow levels possibly rising from around 5500-6000 ft. Sunday morning up to 6000-7000 ft. by Sunday afternoon.
The latest model runs don’t agree on how strong the winds will be on Sunday, but they don’t look to be as strong as the previous 4 days. Highs into the 30s. Most of the precipitation is forecast to fall by Sunday evening with this system.
The low off of the Pacific NW coast is forecast to slowly drop south down the coast through Monday, which could draw in some Pacific moisture with scattered showers possible. Snow levels could be up around 6800-7300 ft. Highs in the 30s. The winds could gust from the southwest up to 50-60+ mph over the ridges.
There will be a boom/bust scenario near the base depending on the snow levels on Sunday. Using the model averages, we could see around 5-10 inches near the base, 8-13 inches near mid-mountain, and 11-16 inches up top for the 2-day period.
Thanksgiving Week:
Another low-pressure center is forecast to be spinning off of the CA coast Tuesday – Wednesday, and is forecast to tap into additional subtropical moisture. That could direct another AR (atmospheric river) of moisture at the northern Sierra as early as Tuesday not until Wednesday.
That could bring in mild Pacific air with another round of rain and high-elevation snow between Tuesday – Wednesday. Then the low is forecast to push inland on Thanksgiving Day, possibly bringing a bigger snowstorm as colder air could work in, how much would depend on the track of the low.
We will be watching this closely over the next several days. We could see rain on top of the snow that falls this weekend, and more heavy snow on Thanksgiving Day. This is a newer scenario on the models so it could change. If we see this storm, rain & snow showers could linger into Black Friday.
Long-Range Forecast:
The long-range models continue to show high-pressure building in near/over the West Coast as we go into the beginning of December. That could bring a pattern change to start the new month, which could be drier and slightly milder.
BA
