Summary:

• Cloudy skies today as a system moves through to our North.  Partly sunny skies Tuesday through Thursday as we have fair weather ahead of a strong storm that will move in on Friday.  

• Friday a storm will push into the Pacific NW and Northern CA.  Rain and high elevation snow should reach the area by Friday evening and last into Saturday.  Still a question of how much precip can spill over into the Tahoe Basin, and what the snow levels will be.  Right now they snow levels look to be around 8,000 ft. on average for the event with several inches of snow possible above that.  

• Another system moves in Sunday night into Monday with more rain and high elevation snow.  We could see several more inches on the upper half of the mountains.

• Things quiet down again next week through mid-month as the ridge rebuilds along the coast.  There are signs that the ridge could shift North beyond mid-month with storms coming underneath into CA the 2nd half of the month.

Details:

The main change over the past 24 hours is that the models are showing a slight shift South with the jet stream by Saturday morning and slightly colder air.  Still expecting high snow levels with the storm coming this weekend, but maybe low enough for decent accumulations above 8000 feet.

Some impressive precip amounts beingn forecasted by the GFS over Northern CA through the weekend.  As we have been saying all week the question will be how much precip can push into the basin.  This will be an ongoing challenge this week with the forecast.  Although the GFS is forecast more precip over Northern CA than the European model, the Euro pushes more precip over the crest into the basin.  

There will be several waves riding the jet into the West Coast that will try to help push the precip in and bring in some colder air with both systems over the weekend.  The first system brings precip Friday evening into Saturday, and the 2nd system Sunday night into Monday.

Here is the 6z GFS precip forecast through the weekend.  You can see the shadowing on the East side of the basin.

This storm is similar to the one at the beginning of December when we struggled with snow levels and how much precip would spill over.  The Euro has less precip over Northern CA, but pushes more over the crest into the basin along with colder air with the wave Saturday morning.  The WPC's precip forecast is similar to that forecast.

The trend South with the jet is a good trend if we want to get more precip and some colder air into the area over the weekend.  On the GFS ensemble height forecast you can see that the ridge pushed a bit further East over the weekend than originally forecast thanks to the strong storm, as the jet stream and trough dig a little further South into CA.

As for the snow level drama....  This will be tricky and it is changing slightly by the day.  The original forecasts were showing snow levels at 10,000 feet or higher through the event as we stayed on the warm side of the jet stream.  Now with the jet sagging further South and colder air pushing in with the waves of precip, we could be seeing lower snow levels.  Right now the freezing levels look like they could be around 9,000 feet Friday night into Saturday morning.  With the heavier precip along the crest and on the West slope we could see snow levels drag down closer to 8,000 ft.  Saturday morning as the colder air moves in as the system departs they could drop as low as 7,000 ft.  With the cooling with the orographic lift on the West slope and the heavy precip they could drop below 8k Friday night.  Across the Tahoe basin if the heavier precip can push in that will help.  With the lighter precip we will likely see higher snow levels.

Between the systems the snow levels jump back up above 10,000 feet.  We should see similar snow levels Sunday night into Monday, with snow levels starting high and falling as low as 7,000 ft. by Monday morning.  Overall the snow levels currently look like they could average around 8,000 feet.  It is only Monday, so this forecast will change by the day most likely as we get closer.  A slight shift North and we could have less precip and higher snow levels.  A slight shift South and we could have more precip and lower snow levels.  A week full of pulling my hair out, and a weekend full of close monitoring of what is happening with the temps.

Above 8,000 ft. where ever the snow line does setup we could see a couple feet of snow over the 3 day period along the crest.  East of the crest it will depend on how much shadowing we see.  We could see anything from a couple inches to over a foot above the snow line.  We are 5-7 days out and I don't talk specific snowfall numbers or snow levels until we are within 5 days.  So we will have a better idea hopefully as we get closer the next few days.

Long-Range:

As the jet stream weakens and the system wraps up by Monday, the ridge will then quickly rebuild along the West Coast.  We will go into another dry period next week into the weekend of the 13th.  You can see this clearly on the height forecast for Friday the 13th...

The trough is back over the cold water North of Hawaii where it was most of January.  There are still signs that the ridge will shift North beyond mid-month, with storms possibly cutting underneath into CA the 3rd week of the month.  

The consensus of the climate models is still that the 2nd half of the month into March is much wetter than we have seen.  

Even though the month of January will be one of the driest on record (the final numbers aren't out yet), it won't be the driest water year on record for the the Northern Sierra for sure.  We already peaked above that with the big storms in December, even though the Tahoe basin was shadowed out on the storms.  We fell below average in January, but we should see another bump up with the heavy precip this weekend over the Northern Sierra.

We do have the snowpack numbers though as of today, and those are pretty dismal.  The entire Sierra is sitting around 22% of average for the this date.

The Top Ten List:

OK, so the results of your votes are in for your favorite activities being done in Tahoe to make it snow.

10.  Booked a trip to ski in another state with snow and it will snow here. Also, thinking about mt biking more and hoping for dry trails...that should add to precipitation.

 9.  Nude Sunbathing.

 8.  Ride. My. Bike.

 7.  Sacrificing snowboarders

 6.  Taking a big dump while praying for one.

 5.  Booking a trip to Europe as it's bound to stop snowing there and start in Tahoe.

 4.  I grew up at Tahoe and in the 70's we were in a snow derth from Dec. thru Jan. Then KTHO began to play a snippet of a Christmas song sung by Dean Martin. They played only the line "let it snow, let it snow, let it snow!" slipping it in between every few songs, prefaced by the announcement: "now a word from the Chamber of. Commerce". After several weeks it worked, snow came down and didn't stop for weeks. So much snow it almost reached the second floor of our two-story house in Al Tahoe! Maybe KTHO needs to try that again.

 3.  We should host a pray for snow car wash. Everyone in town donate a few bucks, get your car washed, donate money to charity. It has to snow on 20,000 clean cars right!?

 2.  I just traded my Tacoma for a Prius. I'm getting it lowered and tearing down my car port. I also shaved my husky because who needs all that hair when its summer all year round.

 1.  I gave up hope. The ridge is fueled by hopes and optimism.

Snowcoming Event:

Don't forget about our event at the 50/50 Brewery on Tuesday night at 8.  We will be hanging out, watching some ski and board videos, and giving out prizes.  Just a fun night to hang out and talk about the how brutally dry the Winter has been, and how brutally snowy we hope it will be going forward.

Stay tuned....BA