Upper Ridge Off Shore and a northwest flow aloft will keep clear skies with cool temps in the forecast the next few days…..Next weather system to bring mainly light amounts of Snowfall for the Towns of Mammoth and June with up to 8 inches possible over the upper Elevations Sunday/Ngt
Thursday November 12, 2015
Posted at 9:13 am by Howard
As mentioned in my discussion below, third paragraph at bottom, I said that the Dweebs were sure that the QPF would be bumped up and low and behold the models did just that. The guidance suggests that up to 12 inches is now possible over the crest.
However, what is not being discussed is that the precipitation is being delayed now by the new 12z WRF until around 12Z to 15Z Sunday AM. If that is true than a lot of the cold air will have had time to get in here and thus we are now looking at a low-end Platinum Powder Alert. In fact considering Orographic’s and Snow to water ratios of 15:1 it may be more like in the 14 to 18 inch range in Saddle Bowl by Monday AM.
I will update this afternoon after the new 12Z ECMWF guidance is out….
The weather will be warmer again today with a little more warming Friday…. (Low 50s) Winds will continue light in town with temperature inversions, whereby lower elevations valleys that are snow-covered will be colder…..day and night. Night time lows over those valleys have been in the single digits the past few days…. So freezing fog is also possible in some areas along the Highway 395 corridor during the early AM hours.
In general, the upper hemispheric pattern is progressive. This is no blocking mechanism over Eastern Canada and so short wave trofs can easily move from the west to the east across the CONUS.
Precipitation amounts in the past weather system were much greater than expected for the central sierra at both short and medium range. In discussion with Retired Lead Forecaster Tom C, it is possible that the models are not factoring in the warmer than normal SSTA’s along the west coast. The Diabatic heating effect of the warmer SSts under a very cold unstable air-mass results in a higher amount of CAPE. (Convective Available Potential Energy) this maybe why there was so much more precipitation last Monday afternoon and night with out a subtropical tap. This is worth mentioning as we have another system that is not as cold as last Mondays storm but has plenty of over water trajectory. Watch the QPF to see if there is changes Friday and Saturday. In the meantime…the Guess is between 2 and 4 inches in town and 5 to 8 inches over the upper elevations Sunday/Ngt. The Dweebs are sure that that will get bumped up by Friday or Saturday.
According to both 6 to 10 and 8 to 14 day outlooks, temperatures will remain below normal through Thanksgiving day.
In the meantime, the GFS has another significant (Cold) upper low off the Washington coast about the 22nd with Snowfall into Mono County Monday Morning the 23rd. Of course this is subject to change and I have not had a chance to see the 12z ECMWF yet…..