Archive for March, 2011

Fair today with light winds…next round of warm air advection snowfall into the high county late Saturday night….

Quick update this morning to highlight that winds will be light today from top to bottom. High temps will range in the 40s in town with 30s over the higher elevations. A beautiful Late Winters Day!

The next round of precipitation has already left the Hawaiian Islands. Subtropical moisture will begin to move into Northern Ca early Saturday morning and then spread south though Central Ca During the Day reaching Mammoth By Late evening Saturday.

The QPF from CRFC is pretty skimpy through Sunday with up to .35 for upper elevations through Sunday night. With the Snow level about 7500 through Sunday, snow will not be much of an issue for the town and even over the upper elevations just a few inches 2 to 4 expected.

The cold front is expected to come through Monday morning just before Sunrise.  So between Midnight Sunday and Noontime  will be the best time for some moderate snowfall accumulations here in town. Some 3 to 5 inches possible here at the village is a good guess at this time with the possibility of about a foot on “Ol’ Woolly”.   Will update Saturday morning for a better estimate.

So another in a series of light to moderate system is expected to bring an freshening of snowfall to the Eastern Sierra.


Here is this mornings guesstimates of the timing of storms into the Eastern Sierra the next few weeks. This is just from today’s operational GFS and is not totally reliable.


1. Thursday night the 10th

2. Saturday night into Sunday the 12th

4. Monday night the 14th

5. Wednesday the 16th

6. Thursday night the 17th

7. Saturday night the 19th into Sunday the 20th.

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Reference Glossary of Weather Terms
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.

MAMMOTH MOUNTAIN PICKED UP ANOTHER 12 TO 18 INCHES STORM TOTAL……NEXT SYSTEM LATE IN THE WEEKEND LOOKS SIMULAR IN STYLE ALTHOUGH IT MAY BE A BETTER PRECIP PRODUCER…..UPDATED TIMING VIA HOVMOLLER

A few linger snow showers are possible this morning. As current system exits….the upper jet still keeps it breezy this morning in the swift WSW upper flow. Upper ridging will build in this evening and diminish winds overnight somewhat. Without any major ridging….there will continue to be clouds and breezy conditions into the weekend.

Next swath of tropical/Subtropical moisture will leave Hawaiian Islands Friday and head for Northern and Central Ca for Saturday. The meat of it really does not get into the Central Sierra until Saturday night with the bulk of it destined for Northern Ca.  This is sort of a replay of the pattern we just went through, except that the colder portion of this next system is colder, more dynamic and negative tilt for Late Sunday night into Monday. Warm advection precipitation with higher snow levels will again effect the Mammoth area Saturday night into Sunday with the snow level plummeting about Sunday Midnight with the FROPA. 1000mb-500mb thicknesses is about 534dm by early Monday am behind the front. Should be good for a 3500 to 4000 foot Snow Level Monday Am.  Best guess….Looks like another foot and a half for the crest. Will update on QPF Friday for the end of the week.

Models are forecasting a ridge over us next Wednesday for some nice weather…..Then timing of next system about Thursday night.

Updated propagation of Amplification “group velocity” of combined long and short wave energy across the Pacific per Hovmoller.

12z 1st-12z 5th Sat AM

12z 4th-12z 8th Tues AM

00z 7th-00z 11th Thu PM

00z 10th-00z 15th Mon PM
Bering sea high remains an anchor feature with series of systems moving across pacific at mid latitudes. Good cold air coming off Asia and resulting cyclogenesis off japan to keep this energy strongly propagating under the high latitude block in the Bering sea. 
The Dweeber……………………:-)


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Reference Glossary of Weather Terms
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.

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…

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………………………………………..:-)



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Reference Glossary of Weather Terms
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.