Monday November 22, 2010
Posted at 9:21 am by Howard
Skies cleared in the Town of Mammoth this morning with the usual “Dave’s Cloud” shrouding the upper Mountain. The mountain received a bonanza of snowfall over the weekend with some 4 to 6.5 Feet reported! Near the village, I received about 3 feet . There will be a bit of a break in the action today….however more is on the way!
The next system has tapped into a reservoir of cold Arctic over NW Canada. It is moving very quickly and will push a front through our area by 00z Wednesday. Snow will once again begin to fall by tonight and become heavy by late Tuesday morning and persist in the moderate to heavy range through 4:oopm Tuesday then go showery Tuesday night.
Here is what the Dweebs want you to know:
1. According to the Monday 12z WRF, The coldest Air aloft will arrive by 06z Wednesday when 700mb temps reach -18c over Mammoth and -20c over Bridgeport.
2. At Mammoth Lakes, 1000-500mb Thicknesses drop to 523dm at FROPA (00z Wednesday) as the Arctic Ribbon rapidly plunges through Mono County before shifting eastward. Although the pure Arctic will be mostly north and east (Over Idaho) It will still be plenty cold!
3. CRFC has updated their QPF forecast to indicate the following:
1. Huntington Lake,Ca 1.21 inches
2. Yosemite, Ca 1.44 inches
So the average QPF for our area would be about 1.33 inches. It is easy to see that at 20:1, the upper elevations could get another 1 to 2 feet by Tuesday night!
Expect another 6 to 12 inches possible in the Town of Mammoth.
Cold and Sunny is the word for Wednesday with Highs in the Upper teens in town. It is “Face Mask” time for you skiers the next few days until the wind quits.
By Thanksgiving day it should be pretty windless by afternoon and we should all give thanks as well for the excellent ski conditions we have for so early in the season. It will be fair and not so cold with highs in the 30s Thursday with lows in the single digits. Friday will be windless and fair with Highs in the 30s lows in the teens and 20s. Expect strong Mtn inversions by Friday.
The Weekend outlook calls for yet another storm by Saturday or Sunday. It is too early to begin speculating on how much snow it may bring. However, one thing is for sure, in that it will not be nearly as cold as the storms we just came through……………………:-)
Dr Howard and the Dweebs………………………:-)
Reference Glossary of Weather Terms
Sunday November 21, 2010
Posted at 11:00 am by Howard
The new 12z Sunday model runs are now complete. They show the main long wave Trof slowly shifting east into the Great Basin over the next 12 hours. The axis of the long wave will be east of Mammoth by 00z Monday. There are two more short waves that will move through the long wave that will effect the Mammoth area the next two days. The first one rolls through early Monday morning and the other during the day Tuesday.
The Monday system has little over water trajectory and so it will be mostly showers beginning about midnight tonight and should be mostly through by sunrise Monday morning. Expect a few inches from that system.
The next and last in the series will have another good shot of Arctic air. It is better organized and has over water trajectory from the British Columbia coast…..south down and through Northern Ca. Although the Northern Sierra is favored with this system, Mammoth Mountain may still pick up another 10 to 20 inches at again, a 20:1 ratio. Expect that the town will receive about half that amount.
Thereafter, a strong northerly flow will effect the high country Wednesday. Expect windy conditions over the crest. It will be sunny and cold in town. An upstream upper level ridge will move on shore Thursday. This will provide fair weather and the best skiing on the most base on Mammoth Mountain, for so early in the season in over a decade!
Although all the global models are not quite in sync yet, using mainly the deterministic ECMWF. It appears that significant height falls will return to the California coast by late Friday night/Saturday morning the 26th/27th of November. This will lead toward the possibility of snow returning to the high country as early as Saturday. The Dweebs believe that snow will become more likely by the following Sunday. This new pattern is not associated with cold Arctic air like the present pattern. It is a more traditional pacific storm with relatively higher snow levels.
However…the screaming message this morning is that the Western Hemispheric Pattern continues to be progressive. And…..without effective blocking downstream, and favorable wave lengths, the storm door should continue to be open for the central west coast into the month of December………….:-)
Dr Howard and the Dweebs…………………………..:-)
Saturday November 20, 2010
Posted at 10:23 am by Howard
Our weather front sailed through nicely early this morning bringing close to 2 feet over the crest and some 10 to 15 inches around town. Short wave ridging will be sufficient to give us a nice break in the heavy snowfall Saturday afternoon, and although there will still be periods of snow, there will also be periods of sun!
The next really heavy snowy period will not develop until very late tonight and more likely after midnight. The period after midnight and before noon looks pretty ominous, as the main upper low moves in and out of California. The upper trof should clear the Sierra by mid to late afternoon Sunday. Expect another break in the heavy snow mid afternoon Sunday into Sunday evening. The next short wave will redevelop more snowfall, again about midnight Sunday night with the last in the series late Monday night.
In between short waves, lighter amounts of either snow or snow showers will still occur. The Dweebs still believe that Mammoth Mountain will get up to 4 feet storm total…..hopefully a little more…..
The high resolution model WRF has the next short wave increasing the snowfall late Sunday night…especially after midnight. Another 6 to 12 inches could fall by noon Monday.
The WRF has yet another colder arctic system the the Dweebs will keep an eye on for the period, midnight Monday night into noon Tuesday. Typically…the WRF beyond 48-60 hours is not as good as the Global models. The GFS has the Arctic low progressing east quicker with no over water trajectory lending to more of a snow showery pattern rather then the wetter WRFs scenario of another 1 foot plus between Late Monday night and noon Tuesday. There will be plenty of time to adjust for this frigid system.
Fair, breezy and cold is the word Wednesday…then little wind in town with strong Mtn inversions developing Turkey day into Friday.
Way off in Fantasy land…..the Dweebs are also keep an eye on a system that is moving into eastern Asia at the moment….. That may become a player in our weather about the time that visitors live for home a week from this Sunday.
Dr Howard and the Dweebs…………………..:-)
Reference Glossary of Weather Terms