Happy New Year! Getting a little bit of a late start this morning from staying up to kiss the bride at midnight. It's a headbanging kind of morning for forecasters with the forecast for next week, and not from having a drink last night. We will get into that in after we go through the pointless clouds, wind, & precip for this weekend...

We start with nice weather Friday morning with mostly sunny skies. Gusty northeast winds from overnight are dropping off this morning but will pick back up from the southwest this afternoon, gusting to 50+ mph over the ridges by evening. Clouds should start to increase through the afternoon as the weekend systems begin to move into the Pacific Northwest.

The Weekend:

This weekend we will see clouds, gusty winds, fluctuating snow levels, and very meager amounts of precip. It needs to either storm with accumulating snow or be sunny. This weekend will be an annoying in-between. We are on the southern edge of a wet pattern from the Pacific NW into the northwest corner of CA that will barely brush the Tahoe Basing Friday night through Sunday night.

Snow levels will be fluctuating between around lake level and 7000 ft. through the weekend. Maybe a tad higher at times, and lowest Friday & Saturday night. Then rising up to 8000 ft. Sunday night. With the meager amounts of total precip if any, we could see a few dustings of snow on teh mountains if showers move through, high-end of 1 inch above 8k NW of the lake along the crest.

The winds will be gusting from the southwest to 40+ mph over the ridges through the weekend. Highs will be in the 30s. It should remain mostly cloudy through the weekend with the precip just to the north. It looks like a gloomy & breezy weekend, and possibly wet at lake level if we see showers.

Monday Storm:

The storm for Monday is still on track This storm will start warm and will be windy for Monday. The precipitation pushes in Monday morning, becoming heavier during the day, and then becoming more showery into Monday evening before ending Monday night. Ridgetop winds increasing to 80+ mph which will likely affect some of the upper mountain lifts.

This storm pulls in a decent amount of moisture before pushing into CA and weakening. The total precipitation range west of the lake along the crest on most of the models ranges from 1.2 - 1.4 inches. The 6z GFS is again trying to play hero with up to 2 inches but has been trending drier the last few runs towards the other models. The average is 1.4 inches but will like come down to 1.2-1.3 with the GFS trending lower.

You can see the precip moves farther south down the Sierra past Mammoth this time. Snow levels could start around 7500-8000 ft. Monday morning and then falling to around 6500-7000 ft. by late morning as heavier precip pushes in. Then with the cold front dropping below lake level by evening and below 4000 ft. Monday night. The GFS has heavier precip falling in the colder air and the Euro in the warmer, so lake level needs a bigger range in the forecast.

The forecast hasn't changed much from yesterday, down about an inch. Based on current trends we may need to chop off another inch tomorrow. It looks like a solid 6-12+ inch storm for the mountains, starting with wetter snow and ending with a drier snow on top for Tuesday morning fresh tracks.

Tuesday:

We should clear out Tuesday morning with mostly sunny skies through most of the day. Highs in the 30s. The wind gusts over the ridges should drop into the 20-30+ mph range, still from the southwest.

Wednesday Storm Madness:

If you are a model rider or a forecaster what happened to the Wednesday storm on the forecast models over the last 48 hours is maddening. After several days of showing the strong zonal jet stream pushing into CA next week, the latest model runs have it not quite reaching and much weaker into CA.

The Monday system still taps into a decent moisture feed, but even that weakens, and now the models show the stream drying up more and more with the Wednesday & Friday systems instead of the strong AR shown earlier in the week.

This is disappointing as we had the storm into the 7-day window before the reversal. Close enough to talk about, but luckily it never made it into the 5-day window so we never got into any potential snowfall amounts. On a global scale, this is a very minor adjustment in the pattern, but major implications for northern CA with the Wednesday storm.

There has been a lot of talk among forecasters at OpenSnow and at other weather outlets I've talked to over the past 24 hours. All have marveled at the big reversal from so wet to some models now completely dry for Wednesday. Some of the discussions have been about the models possibly struggling with the very negative AO (arctic oscillation) and disruption of the PV (polar vortex) possibly triggered in part by the SSW (sudden stratospheric warming).

We don't need to get into all of that, but we have had very strong highs over Asia & record lows in the north Pacific, and a strong high coming to Greenland. This is all just disrupting the typical La Nina storm track around the northern hemisphere and possibly causing the forecast models to struggle with the forecast so much within 7 days and beyond. It's affecting the storms for areas to our east as well into the Rockies where they were also hopeful for bigger storms that have now disappeared.

The GFS & European control models still show the Wednesday afternoon - Thursday morning system holding together. But peaking at the latest 12z GFS run that just came out, it continues to trend weaker. This is looking more and more like we could see clouds & wind with very little snow.

The WPC model shows up to 1.3 inches because it is blending in the wetter model runs.

Instead of 3-4 inches of total precip 2 days ago, the range this morning is down to 0.10 - 1.2 inches. The European & Canadian models showing barely any precip as the system falls apart as it moves into northern CA. I was going to put out an initial snowfall forecast this morning being in the 5-6 day window, with 1-9 inches of snow for the mountains. But looking at the new GFS model it's not worth it until tomorrow. Likely pulling back to 0-6 inches.

Pretty amazing reversal on the models, one to remember (or forget). I was seeing signs of this reversal Wednesday which is why I told you not to trust the forecasts yesterday. Let's not drink the model Kool-Aid for a while. Hopefully not an omen of how the new year is going to start, and just a final FU from 2020...

Thursday - Friday:

We should clear out for Thursday with highs in the 30s. The for Friday, most of the latest model runs have that system falling apart before even reaching the West Coast. Wee Aww...

The long-range models are a little slower to build in the ridge for next weekend. Maybe holding off enough for the southern edge of a weakening system to bring a little snow to the northern Sierra.

Fantasy Range:

High-pressure forecast to build in along the West Coast the week of the 11th through mid-month.

That will shift the storm track to our north. There could be some stronger storms that will try to push into northern CA, but they would have to do it the hard way by busting through the ridge. Oh yeah...

We are watching the pattern trends for the 2nd half of the month. We could be heading back into the more typical La Nina pattern we have seen so far this winter. The new European Weeklies show us on the southern edge of the above-average precip, back to living life on the edge.

The long-range models have been trying to trend the PNA pattern negative 2 weeks out for the last month. The first week of January, then pushed to the 2nd week of January, and now to the 3rd week... The pattern wants to shift to a southeast ridge/western trough in the long-range, but just not getting there yet.

Stay tuned...BA

We have been interviewing our forecasters for insight on their regions on The Flakes podcast. In the latest episode, we chat with our Pacific NW forecaster Larry Schick, & with Paul Fremeau about forensic meteorology. Some interesting stuff!