Weakening system over the southland may give some snowshowers Thanksgiving day and night….Cold Arctic System makes its way into the Pacific Northwest with Arctic air to Accompany….Snowfall may begin as early as Monday for the Mammoth Area…..
Wednesday November 27, 2013
Posted at 6:25 am by Howard
Wednesday AM Update:
The Thanksgiving holiday weather looks mostly cloudy with a slight chance of snow showers both during the day and night. Daytime highs in the 40s and nights in the teens and twenties. The rest of the weekend look party cloudy with little temperature change. Winds will be light……
Last several runs (Tuesday and Wednesday) of the ECMWF and GFS still have quite the powerhouse coming into the pacific northwest early next week. However, an adjustment eastward in the pattern suggests that the upper center is likely to remain over land now and not out over the sea. Nevertheless, plenty of upper jet energy will bow out off shore and then into the Sierra next week, so still a good possibility of significant snowfall. There are even some signs of a tropical tap later next week. The Key on all this is this. Recent models run of the GFS has the upper ridge axes at 140west through Alaska. The ECMWF has the axis about 145 west. The 140W longitude line for California is Critical. Often times when a long wave highly amped ridge is east of 140W…Storms take a track over land, where by if the ridge axis is west of 140W the track is offshore. The ECMWF is still west of 140W, however, not by much. So a lot will depend upon the eventual placement of the upper ridge when it sets up next week for how much snowfall we get. The Dweebs have noted that the ECMWF is a better global model when looking out a week then the GFS….
This is an evolving situation in which it will probably not be known, how much snowfall will occur until Sunday for the up coming week. There is no doubt that we will get snowfall. The question is how much and….there is plenty potential for Footage IE 1 to 3 feet over the crest……The Dweebs will not update again until Sunday…….
Have a Great Thanksgiving and Travel Safe!
Dr Howard and the Dweebs……………………………………..:-)