Archive for February, 2012

Strong Winds Continue In The High Country…..Expected Amounts Still Look Like 6 to 12 Inches Over the Upper Elevations Through Thursday….The MJO Continues In Its Active Phase….

Back to reality…..

New CRFC QPF has come in drier beginning at 4:00am over the next 48 hours showing 1.21 inches for the Yosemite Valley…..Huntington Lake .61

That is a good 1/3 less than it showed yesterday PM.

Additionally…..The way this system is coming in at this latitude, it favors the west side up to the crest with amounts diminishing rapidly as you go east of the crest. That is because the active precip phase of the upper jet’s axis is to far to the north…and there is no additional moisture being advected in from the south. The system is totally dynamically driven…All the moisture is coming up over the eastern pacific ridge west of Hawaii, and none of it is being advected from the southwest off the Ca Coast.

Currently the nose of 130knott upper jet is inland just north of the Bay Area and will push southeast and….at the sametime translate east. This is one of our windiest patterns here in the high country. All in all by Thursday Pm we still have the chance of getting a foot over the upper elevations….

This weekend looks fair with warmer temps. Highs in the low 50s Saturday/Sunday.

Outlook:

The next system on Tuesday is another NW slider so it may bring a few showers along with wind and cooling…….

The following system down the road to keep an eye out for is the March 9th storm….then another on the 11th….

Another may follow around mid month….

MJO:

Is in its active phase and effecting the pattern over the pacific by a flip in the PNA index to negitive. That is a big reason why it is stormy here in the Sierra.  Retrogression has occured to an extent. However, a bit more is needed to get the long wave far enough to the west for the upper jet to come in to the south of us. The Dweebs believe that over the next week or two, that is possible. This is based on the dynamical models from the operational global prediction systems, forecasting the MJO, remaining active and moving over the warmer waters of the Indian Ocean, then east to the Martitine Continent. However, if the MJO stalls or weakens contrary to the forecasts that would be siginfcant.

 

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.

Very Windy System Headed For The High Country….High Wind Warnings Hoisted This Morning Beginning 7:00am Wednesday….6 to 12 inches of New Snow Expected for Upper Elevations Wednesday……Future Pattern Showing Several Trofs Effecting West Coast Over The Next Two Weeks….

3:30PM Update

Still shows a wetter system for Mammoth then what the Zone forecast from NWS is indicating for Mammoth… The updated QPF from CRFC has 1.95 inches for the Yosemite Valley Through Thursday Night. The Updated QPF for Huntington Lake is 9 tenths. So if your conservative and add them, then divide X 2 you still get 1.43 inches. Considering the temps…..at ratios of 12:1 that’s “about” 17 inches over the crest by Thursday Night.

Gee the local guys might even get a double plow?

From this AM:

A Nice Baroclinic Leaf has developed this morning off the coast of the pacific NW. This is a sign of a rapidly deepening upper Trof. The nose of 120Knott upper jet is approaching Northern California and will come in Just north of the Bay Area then across to Tahoe.  Models coming in wetter this morning….Tahoe will get the lions share of snow with this one with up to a foot around the Lake and some of the guidance suggesting 3 to 4 feet in the Mountains NW of the Lake though Thursday.

The southern portions of Mono County will be under the Front Right Exit region of the upper jet during the best forcing…. The QPF stated by CRFC is showing 1.2 inches for Yosemite with amounts of .46 at Huntington Lake through Thursday. The freezing level is about 5K. So the Snow will be pretty dry and will fluff out. Mammoth is between these two area but a bit closer to Yosemite. So considering the freezing level, Mammoth Mt could get between 6 and 12 inches of snowfall between tomorrow Am and Thursday Ngt. The area between 395 and the Village between 2 and 6 inches…same time frame.

Winds will be important to note as gusts in the 50 to as high as 80 mph in the windiest areas are possible Wednesday for travel along the highway 395 corridor. Winds over the crest are expected to reach 115 to 120mph Wednesday into Wednesday night. High wind warnings go into effect for Mono County at 7:00am Wednesday and at 10:00am for the Owens Valley. The Owens Valley will experience strong down-slope winds in excess of 60 mph later in the day Wednesday…..out of the WNW. Winds will peak about dinner time…..then slowly decrease…..

 

The outlook for this weekend is for fair weather with 8000ft temps in the 40s…lows in the teens and 20s with light winds….

 

 

Dr Howard and the Dweebs……………………….:-)

————————————————-
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.

Small weak system brings light snow to the high country….Then Strong WNW Sider Brings Strong Winds And Much Cooler Weather With Additional Snowfall…..MJO on the Move again!!

Monday PM update:

New 18Z GFS has nice system for the Sierra on the 6th of March.

Will check and see in the morning if the 00z and 06z Run has it as well.

 

Monday AM.

A band of Snow developed within the area of surface convergence (Deformation) has brought snow to the Northern Sierra and may dump up to 10 in some of the west side resorts with 4 to 6 along some areas of Tahoe.  This is a change to earlier forecasts. Next upstream system will bring a good 1 to 2 feet along the west side resorts Wednesday….

At the Moment snowing lightly in Mammoth…forecast still looks good today with generally light amounts within the 2 to 3 inches range for the resort levels of Mammoth Lakes.

Next upstream system is looking very windy for the high country…. Winds in excess of 100mph are expected Wednesday….with gusts in town and along the highway 395 corridor 50-60mph….  This Mornings WRF shows in increase of amplification with the upper jet becoming more NW orientated with time. Again this is a windy bugger….precip overall looks like in the light category (3-6) will update today, as more guidance come out.

Best guess…..totals from todays storm and Wednesdays 5 to 10 inches over the upper elevations……However, if the mid week system shifts justs some 50-miles to the south…amounts could exceed a foot over the crest.

MJO:

MJO’s on the move again but so far, its strength is not all that impressive. However…over the next week the NCPE is rapidly increasing its intensity….  The models are beginning to pick upon it….

SEE: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ncpe.shtml

Additionally….the PNA index has in fact gone negitive at the sametime MJO is at 60E with an extension at 95E. The PNA is probably responding to the increased convection over the Indian Ocean.

More Later….

The Dweeber……………:-)

————————————————-
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.