Summary:

Cold front will push through the area today.  Snow will break out this morning and last through this evening.  Temperatures will fall into the 20's and 30's behind the front today and teens tonight.  We could see a few inches of snow at lake level and several inches on the mountains by tonight.  Cold weather Monday before temperature rebound to seasonal averages the rest of the week.  

Next weekend we may see some colder air move back in from the North but precip chances look low.  Another cold shot of air may push in around Thanksgiving, again with a low chance for any precip.  The ridge of high pressure in the East Pacific blocking storms the next 2 weeks may begin to break down by the end of the month.

Details:

I have been watching the storm move in overnight and watching it tilt.  The snow has begun falling in Kingvale as of 7 a.m. on the West slope.  The snow will push into the basin during the morning hours.  The winds are out of the South and the front continues to tilt back as the trough digs Southeast.

Watch the evolution starting with 24 hours ago...

12 hours ago..

And as of 615 a.m.

The forecast models were showing this but a not quite as tilted until yesterday afternoon.  What it does is has the winds from the South was the front moves through.  The Sierra face Southwest so for the best orographics and spillover into the basin you want some sort of Westerly component.  The front is strong through and will push the precip into the basin.  There will be a lot of shadowing though East of the crest.

The GFS was the first to start pulling back precip amounts East of the crest yesterday and continues this morning.  The Canadian forecast model is as well, and the NAM.  Only the European model showed the same amount of liquid across the basin as the original forecast on its latest run.  Here is the latest GFS total precip forecast.

Using this run I would forecast up to 1 inch at lake level on the East side of the lake, 1-3 inches down the center of the basin, and 3-5 inches West of highway 89.  For the mountains 1-3 inches on the East side of the basin, and 3-6 inches on the West side, with up to 8 inches possible along the crest above 8000 feet. 

It will be interesting to see what happens as the front moves through, and what happens with the convective snow bands behind the front in the cold unstable air that could setup and drops a few inches of snow quickly.

After this 3rd storm in a row to start the week we look to have a break as high pressure builds off the coast.  At first the ridge is flat with more storms into the Pacific NW.  Then it shifts North and West by next weekend possibly driving colder air down from the North in to CA.  The GFS shows this while the European model has the ridge a bit closer to the West Coast and the coldest air East of us over the Rockies.

Long-Range:

The GFS Ensemble runs show the ridge amplifying North and driving more cold down the West Coast by Thanksgiving.

If you want to get an idea of how frustrating it can be to try and use forecast models in the long-range, here is the Canadian model for the same day and it's similar to the European model as well.  They are showing the ridge further East and the cold trough over the Central U.S. instead.

Even within the same model you get discrepancies.  Here is the GFS ensemble mean run for the end of the month showing the ridge breaking down and a trough digging into The Eastern Pacific.

and here is the GFS ensemble control run for the end of the month showing the ridge still strong over the West Coast...

Let's hope that the ridge at least amplifies North far enough off the coast over the next 2 weeks to at least bring us colder air, and maybe some moisture off the Pacific for some snow.

Stay tuned....BA