Snow and Chains In California's Sierra Nevada with Rain Returning to the Northwest

It only happens once every 5-10 years:  substantial snow at pass level in California's Sierra Nevada mountains.  Enough snow to require chains.

Snow even go to the level of Lake Tahoe (see pic)

And up to a half foot below 7000 ft.

So cold that the temperature at 5000 ft (850 hPa) at Oakland, California tied the record for the date! (the circle shows today's temperature at 5 AM).  Impressive, most impressive.

Why is this cold and precipitation, so unusual for this season, hitting California?  The reason is that an amazing area of low pressure moved into California (yes, the low that hit us first!).   Take a look at the 500 hPa forecast for 2 PM Sunday.  Just amazing...you would think it is February.

Will the weather gods relent in sending winter weather to the West Coast?   The answer is no.  Here is the upper level chart (500 hPa, around 18,000 ft) valid at 11 PM on Thursday.  A very long Pacific jet stream (where the lines are close together) is aimed directly at the Northwest.  This is a January pattern not a mid-June one.

 And with strong flow approaching our region from the west, substantial precipitation will fall north of the CA border.  2-5 inches along the Vancouver Is. coast.

Some folks have been worried about a lack of rain during the past few weeks over western WA....they will soon stop worrying.  

I should have known this bout of winter would occur...I put in my tomato plants over the weekend.

from Cliff Mass Weather and Climate Blog http://ift.tt/2rkp2k0