Wednesday Nov. 25
A low pressure system that brought snow to the Tahoe region late Tuesday and overnight has moved into Nevada this morning but has left scattered snow showers in its wake. It looks like the accumulations so far have been on the low end of the forecast range — closer to 12 inches at the Sierra Crest than 18 — with about 6 inches at 7000 feet. A few more inches of snow are possible today in favored locations as the showers wind down.
The low pressure will remain over Nevada for the next several days, with cloudy to partly cloudy skies likely and snow flurries at times. The low is forecast to lean back toward the Sierra Friday and Saturday, bringing a better chance of showers strong enough to lead to measurable accumulations. Temps will remain on the cold side through the weekend.
The next chance for serious snow will be next week. A fairly strong low is forming in the Gulf of Alaska and is forecast to move our way by the middle of next week. One of the models has this system taking a direct hit on the Northern Sierra, which would be promising for snow watchers. The other model, however, shows it drifting south over the Pacific before turning inland above Southern California. That would mean a lot less, if any, snow for us.
So we will be watching this system as it exits and the next one as it takes shape and finds a trajectory that it likes.
We will let you know what we learn. Stay tuned!
Tuesday Nov. 24
A winter-like storm that should prove to be the best of the season so far is moving into Northern California this morning and should bring snow to the Sierra by this afternoon.
This system and the current atmospheric conditions are a bit complex, but they appear set to bring snow and cold temperatures to the region off and on for the rest of the week and into the weekend.
The main event will be today and tonight, with 12 to 18 inches of snow possible at the Sierra Crest, about a foot at 7000 feet and 4 to 6 inches around the Lake by Wednesday. Temperatures will be about 15 degrees below normal as cold arctic air flows into the region, with highs in the 20s and low 30s. Snow levels are likely to dip down close to or even below 2000 feet by Wednesday morning.
The low pressure will move into the Great Basin east of the Sierra by late Wednesday, but it is forecast to stall there over Thanksgiving before drifting back to the west. As of now it appears likely to come far enough west to bring a new round of snow showers to the Sierra Friday and Saturday. These will likely be scattered with more modest accumulations, but we could still see several more inches of snow by the time the main low exits the Sierra for good late Saturday or Sunday.
But the storm door will remain open, and another system taking shape in the Gulf of Alaska could reach Northern California by Tuesday.
Stay tuned for details.
Monday Nov. 23
The fourth winter-like storm in four weeks is still on track to move through the Sierra this week, and the details are starting to come into focus. This will be a cold storm with a modest moisture plume and very high snow-to-water ratios. It looks to leave us with a very White Thanksgiving.
The latest forecast models show the system approaching Northern California Monday afternoon and evening and moving into the Sierra overnight.
We should see snow by Tuesday morning or mid-day in Tahoe, with snow levels starting below the passes and dropping from there. By Tuesday night when the coldest air arrives snow levels will drop to 3,000 feet and perhaps even as low as 2,000 feet.
With limited moisture, this won’t be a massive dump of snow. But those cold temps will turn most of that moisture into snow, so we should see another 4 to 8 inches above 6,000 feet and at least a foot, maybe a bit more, above 7,000 feet. In places south of the Lake, lake-effect snow could enhance those numbers as moisture from Tahoe gets swept up into the storm and returned as snow.
Scattered snow showers will probably linger into Wednesday and cold temperatures will continue through the holiday. It also looks like the low pressure system could even sag back toward the Sierra and bring another round of accumulating snow on Thursday or Friday.
A new system, meanwhile, will be forming behind this one and could make it to the Sierra by the end of the Thanksgiving Weekend.
Stay tuned for updates.