One Last shot of Snow and Rain from the Subtropical Jet Today then Pattern Change this Weekend leading to a Cool and Dry weekend and beyond…..
Wednesday December 5, 2012
Posted at 9:16 am by Howard
The last in the series of subtropical jet related systems to effect Mono County will arrive later today. Gusty winds have been blowing most of the night and will continue to do so throughout the day. The snow level will be about 8700 today down to 8300 tonight. Over the upper elevations,A few inches of snow will fall by Midnight tonight.
The next pattern change occurs Friday as the current cold low in the Gulf of AK weakens and ejects ESEward into the pacific NW while a full latitude ridge builds northward about 140W and takes its place by Saturday. So the change that is in the offering is that we get rid of the Subtropical jet and mild WSW flow to one of which comes from the extreme northwest pacific which will have continental air mixed in with it. For the Sierra, this is a drier pattern with impulses next week dropping into the Great Basin via the Pacific NW. (There is always a chance of a few snow showers if an impulse get far enough west to effect us.) Expect Arctic Air dropping south over eastern Washington state eastward through Montana….making for a storm track NNW/SSE over the Rockies with light snowfall favoring the Central Rockies like Colorado Saturday afternoon/night.
Drier continental air in December usually makes for much colder mornings here in Mammoth, with daytime temps between normal and below normal. Highs will cool into the 30s by weeks end. Nights in the upper teens and low 20s. Temperature inversions may set up with some temps over colder valleys like Bridgeport/Bodie dipping down into the single digits next week. As a surface high drops SSE from BC, Canada into the northern Great Basin, Off-Shore flow develops Sunday for California. Southern Ca WX looks marvelous Sunday…..A Day at Disneyland?
So far the action next week stays over the Rockies then pushes even further east to the Northern Plains with the Northern Plains states experiencing there first real shot of Arctic Air this Fall…. However…more importantly…..it will be interesting to see where the Arctic air will go afterwards….
Will the -AO team up with the NAO by it too going strongly negative. Will a high latitude block set up over Greenland and a deep Hudson Bay Low, giving all the Weather Weenies over New England a Solstice Treat? Or…..will the main PV descend over AK with retrogression of the eastern pacific high, providing a good old fashion Sierra Snow storm the days following the Solstice? Time will tell……………………The Dweebs got you covered……
Dr Howard and the Dweebs…………………………..:-)