It appears that we will be entering into a very cold unsettled period relative to the season. The current long wave trof will slowly make its way toward the west coast this week. The first salvo is currently bringing strong gusty winds along with the beginnings of a cooling trend for the high country today Tuesday. The first cold front moving through Wednesday afternoon is expected to be very dynamic. Although PWA is not expected to be all that great for the Sierra, the strong UVM  should more then make up for the lack of deep moisture. The storm is expected to bring up to a foot and a half  to the Village, the period beginning   Wednesday though early Thursday morning.  The following system within the long wave is being handled differently between the ECMWF and the GFS.  The GFS is quit a bit slower as the system spins up a surface system off the south central coast.  According to the 12z Tuesday GFS…..There appears to be a three impulses of interest. Two strong impulses within polar jet with Maritime air. The systems are along 140west and the lead at about 38 north at 4:00am Thursday morning. There are two distinct jet-lets with these little jewels. The lead has 130 knots at 300mb as the jet turns the corner eastward with the other still coming down the pike at 50n. The two system combine later Thursday PM with the upper jet heading for Southern Ca as a  cyclonically curved upper jet into Southern Ca by 4:00pm Friday. Considering 500-1000 thickness falls Friday night to 540 then 534 dm…. and the front left exit region over the San Fernando Valley NE through the Antelope Valley it could get interesting for snowfall through the grapevine and all along Highway 14 through portions of the Mojave desert/Lancaster later Friday night. No doubt the southern portions of the Owens Valley and possibly northward could be under the gun for snowfall as well.  A swath of 90% RH at 700mb extends up the Owens valley as well as thickness as low as 1000-500mb thicknesses of 534dm by Saturday am. The third impulse will keep our air-mass cold and showery Saturday.

Outlook:

The  upper level long wave is slowly progressive and shifts into the Great Basin about the 20th of February. There after,  if the proggs are correct…either west coast sliders or even California sliders will continue the trend of cold, light to moderate precip producing storms depending upon if there is over water trajectory or not, until the next significant period of central pacific amplification takes place toward the end of the month.

Dr Howard and the Dweebs……………………..:-)



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Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.