Arctic Born Storm to test forecasters abilities along the coastal sections of the Bay Area northward as Snow Levels may drop below 1000 feet Friday…..Up in the Sierra, this will be a powder event with very cold temps Friday night into Saturday.

Sierra Forcasters will have a somewhat easier time with the forecasts the next few days as the precipitation that falls over the Mono County Area Friday and Saturday will certainly be all snow! Questions still remain about how much snow will fall as the system  itself  is currently pretty dry but will pick up moisture as it develops off shore. The QPF from California Rivers Forecast Center paints about an inch and a half over the crest by Saturday AM, giving the upper elevations a good 2 to 3 feet. This is considering the cold nature of the storm and the potential ratio of snow to water….. 20:1 to 25:1.  The big question remains about the possibility that this system may tap some deeper moisture from the central pacific Friday that would help boost QPF totals….hence this is still a very much developing storm that may prove to be a bigger precip producer for the high country than what the models are currently showing. Of course, if it does tap central pacific moisture, that may moisten the system up a bit with the ratios not quite as high as we currently expect.


What We Know:

1. A very deep upper low will form off the coast of Vancouver by Thursday Night

2.  This upper trof will then sag southward just off the coast of the Columbia River by early Thursday and continue to shift southward down the west coast through Saturday Morning. Deep layered onshore flow will exist in the mid and lower levels for a prolonged period of time….. and so what we will experience is really one big ocean type Lake Effect into the sierra beginning Thursday night into Friday afternoon. If the central pacific moisture gets tapped, that would be the bonus.  So again….A combination of onshore flow, UVM, orographics and strong upper jet dynamics will keep this a major storm to contend with. At the moment, a good 2 to 3 feet of snow is certainly possible by Saturday morning. Will update on the estimated amount of snowfall Thursday morning.

3. The other big issue here is the Arctic air dropping in over California from the north instead of back dooring us from the northeast. The new 12z WRF has -18C over Mammoth Mountain at 10,000 feet Saturday mid morning. That is -4 F. and temps in the town of Mammoth will probable be in the low single digits Saturday morning. Any wind at all will create a significant wind chill factor Saturday. Up slope conditions may develop Saturday afternoon into the evening.

4. The best part of this storm is that it is pure Western Canadian Born. In perspective, it is rare that Mammoth gets the potential for large amounts of snow at ratios of 20:1 to 25:1. Saturday for those that want to experience deep cold dry powder will want to have the right warmth for the elements. And  to experience the possibility,  of true Canadian type powder! 


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.

Increasing Clouds Today….Snowshowers Possible Late Today and Tonight…..Champagne Power Alert For Next Weekend!

It was a cold one this morning…-11 at the Mammoth Ap and -7 at Crestview. The combination of strong radiational cooling, the existing snow cover and low dew points allowed early morning temps to fall to low levels. Temps in the Town of Mammoth were as low as 0 F  this morning.

Latest RAMSIS showing  snow showers over the Northern Sierra and the leading edge of a cloud band that is currently over Alpine County to our north. This leading edge of the cloud shield is shifting south and will begin to increase cloudiness in Mammoth either later this morning or by this afternoon. Since the system is tracking so far west, little or very light amounts of snowfall is expected.  A scant to in inch possibly tonight. Tuesday looks partly cloudy with  highs in the low 30s.

Wednesday will be dry with highs in the mid 30s.

The next system is still being handled differently by the both the EC and the GFS. They have sort of flipped flopped in there thinking. Now the GFS is slower and tapping subtropical moisture from under the ridge.  There is strong blocking pattern associated with this storm and the system will also be tapping very cold Arctic air from a sizable pool up over the NW territories. Some of the coldest air of the season will be released into the far west into the back of this storm, and so the second half of what we get will be very light and powdery. The real question at this point is how quickly it will move through. The slower track will allow for more snow to accumulate. The models at the moment range from 1 to 2 inches of QPF.  But that is significant, at snow to water ratios of 15:1  to 20:1. Once again, more time is needed to fine tune this storm.

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.

Blue Bird Morning in Progress….Storm Total On Mammoth Mt 5.5 to 7.5 Feet!…..Over 3 Feet in Town

Mammoth Mountain reports storm total 64 to 92 inches!

Some areas on Mammoth Mountain approaching a 20 foot base!


The Dweebs received reports from locals of the best powder of the year so far as the top of Mammoth Mountain opened Saturday. The weather maps this morning indicated a short wave ridge over the area  keeping us precipitation free today. Crystal clear ultra blue skies this morning were expected to cloud up somewhat later today as there was enough cold unstable air aloft for this reason. High temps today in town were expected to be near 30 degrees with lows upwards to the mid 30s on Washington’s Birthday.

The next weather system appears to be developing far enough west off shore to keep most of its precip out of our area. Although there will be plenty of cloudiness, and some possible snow showers Monday night or early Tuesday Am…..The main effect of this upper low will be clouds and some increase in wind over the crest. Temperatures early next week will remain below normal in this NNW flow aloft upper air pattern.

Longer Range:

The longer range looks more interesting. Last nights 00z global models had significant differences. The Canadian and American GFS has a very cold plunging upper trof that will bring mainly light to moderate amounts of snowfall to the Eastern Sierra Thursday/Friday. The European on the other hands forms a closed low up off the coast of the Pacific Northwest which allows the upper pattern to bow out off shore and tap subtropical moisture from under the upper ridge north of Hawaii. The latter pattern is slower and wetter pattern while the former pattern is colder and dryer.  The ensemble’s favor the colder dryer scenario at this time. However, the very new 12z Sunday GFS run just took a turn to follow a match more like the European. Whether this works out is still unknown at this time as this is quite a change from the number of GFS runs showing the former colder dryer scenario.

Stay Tuned, the Dweebs have you covered!………………………………..:-)

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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.