Steady Heavy Snowfall Has Turned To Showers Now As Long Wave Shifts Into The Great Basin
Sunday November 21, 2010
Posted at 11:00 am by Howard
The new 12z Sunday model runs are now complete. They show the main long wave Trof slowly shifting east into the Great Basin over the next 12 hours. The axis of the long wave will be east of Mammoth by 00z Monday. There are two more short waves that will move through the long wave that will effect the Mammoth area the next two days. The first one rolls through early Monday morning and the other during the day Tuesday.
The Monday system has little over water trajectory and so it will be mostly showers beginning about midnight tonight and should be mostly through by sunrise Monday morning. Expect a few inches from that system.
The next and last in the series will have another good shot of Arctic air. It is better organized and has over water trajectory from the British Columbia coast…..south down and through Northern Ca. Although the Northern Sierra is favored with this system, Mammoth Mountain may still pick up another 10 to 20 inches at again, a 20:1 ratio. Expect that the town will receive about half that amount.
Thereafter, a strong northerly flow will effect the high country Wednesday. Expect windy conditions over the crest. It will be sunny and cold in town. An upstream upper level ridge will move on shore Thursday. This will provide fair weather and the best skiing on the most base on Mammoth Mountain, for so early in the season in over a decade!
Although all the global models are not quite in sync yet, using mainly the deterministic ECMWF. It appears that significant height falls will return to the California coast by late Friday night/Saturday morning the 26th/27th of November. This will lead toward the possibility of snow returning to the high country as early as Saturday. The Dweebs believe that snow will become more likely by the following Sunday. This new pattern is not associated with cold Arctic air like the present pattern. It is a more traditional pacific storm with relatively higher snow levels.
However…the screaming message this morning is that the Western Hemispheric Pattern continues to be progressive. And…..without effective blocking downstream, and favorable wave lengths, the storm door should continue to be open for the central west coast into the month of December………….:-)
Dr Howard and the Dweebs…………………………..:-)