Mammoth Mountain Reports 4 to 6 inches this morning with another foot forcasted by Thursday…..An Active pattern is likely to continue for the next week or two…
Wednesday March 2, 2011
Posted at 9:07 am by Howard
The nose of 110knot subtropical jet moved into Ca early this morning increasing precipitation once again. The snow was wet in town with a few inches of new on the ground. It will be an unsettled day today with steady snowfall in the morning then becoming more showery this afternoon. The cold front associated with this pattern will move through about 10:00pm tonight with snow levels lowering to the Mono County valley floor. Latest CRFC QPF for Yosemite, the period between 4:00am Wednesday and 4:00am Thursday is .80 so another 10 inches is possible over the crest and some 3 to 5 inches in town today. The following QPF 24 hours period is about .25 inches. So we may get another 2 to 4 inches of snow additionally Thursday over the crest. That snow will be lighter……
Quick Update: 9:00am: The IR loop is showing a lot of the mid level activity thinning out over the central valley. SFO Radar is showing a lot less activity moving on shore. Looks like the steady snowfall maybe coming to an end and the more showery pattern for today beginning shortly.
It appears that we will remain in an active pattern for some time now. Possibly a week or more ????
The most recent ensemble mean of the ECMWF shows an upper ridge location extending from the northern and eastern parts of Alaska southeastward across BC, Can. The westerlies extend underneath that block stretching from south of Kamchatka, Russia…across the Aleutians to near Vancover Isl. Additionally the main PV anchor is situated over Eastern Canada…Greenland and Iceland. This span is certainly conducive wavelength wise, for the continuation of the train of west coast short waves that will effect central and northern Ca northward for another week or possibly two? The trend in temperatures next will take a bit of a dive next week. It should be cooler than normal.
Western Pacific Action: + (Explanation)
Looking at the latest western pacific cyclogenesis starting the timing when the leading cyclonically curved isobar crosses 150E. The following timing is as per (96 hr) Hovmoller from Canadian or GFS north pacific sfc progs.
1. On the 120hr from the new Wednesday 12z GFS surface to 500mb thickness, Surface system spins up with leading isobar crossing 150East sometime between midnight and 4:00am on Monday the 7th of March. Energy should propagate through the West Coast Early Friday morning the 11th of March. (FROPA)
2. Next note worthy surface system timing is 12z on the 15th for a FROPA throught the west coast the morning of March 19th.
(Note: This is really pushing it time wise) The pattern may be ridged up by then……we”ll see.
(This timing is for amplification energy and not for moisture timing which can be caused by warm advection overrunning ahead of the dynamic forcing. In most cases the Hovmoller timing is more in line with the PVA or cold front timing)
Dr Howard and the Dweebs………………………………………..:-)
Reference Glossary of Weather Terms
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