Archive for December, 2022

Nearly Zonal Flow pattern from Japan to the west coast with series of Wet Storms impacting the Sierra the next two weeks….QPF 7 to 8 inches by this weekend west of our Sierra Crest…..


Heavy Drought Busting Precipitation is forecasted the next two weeks as a series of Atmospheric River’s are associated with and proceed most weather systems. This pattern will keep folks that are dealing with avalanche dangers on there toes as each wet storm contains a period of colder temperatures both before and after for lower snow levels between rain events, mainly below 9000 feet.

Some of the deterministic models are forecasting 25 to 30 inches of water over the next two weeks just west of the Sierra Crest. However remember, guidance is not a forecast and the models can change in a week.

This is truly a drought busting pattern if it continues weeks in the 1 through 4 week inter seasonal outlook,  as the Climate Forecast System model suggests.

Mammoth Mountain at the Main Lodge picked up 33 inches snow total at 9000 feet. Higher amounts most likely in the colder temps, certainly possible at 10,000 to 11,000 feet.

There will be a break today, then the next more potent AR arrives Thursday with initially snowfall for the town, before snow turns back to rain Friday Morning.  The snow level is expected to rise to between 8500 and 9000 feet down here in Southern Mono County Friday.  The snow level will come down again Saturday later Saturday morning with very heavy rain or snowfall amounts in the Town of Mammoth,  into the night.  The latest RFC QPF is for 7.5 to 8 inches of water, due west of the Sierra Crest..  It should be dry for New years Day and night with just some lingering snowfall in the morning hours. Conceivably, this could be a 5 to 6 foot snow maker above 9500 feet.



Dr Howard and the Dweebs…………………:-)


As of 9:50AM Monday, a level 4 AR is expected to make landfall over Central CA Tuesday AM… Copious amounts of precipitation is expected to bring both rain and snow to the high county. Snow will change to rain tonight then heavy rain is expected below 9000 feet after midnight tonight through Friday AM. Cooler air will move in an lower the snow level by mid late afternoon to 7000 with the snow level lowering to the valley floor of Mono County Tuesday night. 5 to 6 inches of water is expected from this first storm. Any precipitation Wednesday night will be snow in town. However, yet another AR is expected to move in Friday into early Saturday AM with rising freezing levels up to 9000 feet. The freezing level come down later Saturday afternoon.  Total QPF the next 7 days is about 10 inches over and west of the crest. Another 7 to 9 inches is possible over the following week…


More later………………………

Dirty Ridge Continues to allow weak systems to bring considerable high clouds, breezes and mild temps to resort levels…..Longer Range Model trends keep the AR possibilities for next week…..Latest modeling suggest trend to wet January

It will be a fine morning for the last few hours of Fall. Winter Solstice occurs at 1:48pm. Expect Sunny Sky’s today Wednesday with highs in the 40s with gusty winds this AM over the crest and some early day breezes in town as well.  Tomorrow Thursday shows increasing high clouds. Breezy again with highs in the 40s. There will be a slight chance of some light snow Thursday night. Then dry through Monday including the Christmas holiday with highs pushing into the mid 50s and lows in the upper 20 to low 30s Sunday and Monday.

Extended Outlook:

Thoughts about next week.

As of Thursday morning, a strong Level 3/4 event is being forecasted along the central coast and inland with borderline level 4 for coastal SFO. The peak of the AR is about Midnight Tuesday night.  Snow levels will be coming down during the day Wednesday.  Quantitated Precipitation” 7 day outlook is for 4 to 7 inches of water over the upper elevations, Tuesday into Thursday.

Antecedent conditions are very favorable for a heavy Rain/Snow event.

1 Portions of our Snowpack is currently partially dry snow,  so it will have the ability to absorb a lot of any rain that may fall.

2. Creeks are very low due to the ongoing drought.

3. Reservoirs state wide, are very low and can handle a level 3 AR+ with no issue. However, there is always the possibility of some local street flooding.

4. The *IVT ramps up Tuesday afternoon and peaks out Tuesday midnight. Expect high winds Tuesday and into the night.

5. Local Aviation on Tuesday will have issues due to strong winds and turbulence. If they are flying and your with them, be sure to have your barf bag handy. 🙂


Integrated Water Vapor Transport (IVT)

Interesting to note that the AR on the central coast is being fed by not one, but two streams…         Old WX man saying….Don’t fool with an AR whom has forked transport

Beautiful Weekend on Tap with Strong Inversions and Mono Lake Fog to continue in the Lee Vining Area until winds pick up Tuesday or Wednesday…..It will be milder over the Christmas Holiday then something to watch out for toward New Years….


No significant changes this morning to yesterday’s thinking.  It’s a wait and see this week for next weeks mid week storm.

On another note, it’s been touted that we will have a dry January.  The Dweebs are not so bullish about that this morning. The NCEP Global Ensemble System extended forecast shows a significant MJO migrating into Phase 7 the second week of January. The Dweebs believe that there is a significant chance of a “Mid Latitude Response” leading to an active pattern for CA around that time. The reasoning for that thinking is that during November, the MJO succeeded in generating a downwelling oceanic Kelvin wave, which is reducing the extent of the available cold water that the trade winds can upwell near the date line. This may have the effect of allowing the MJO to extend eastward, stronger and thus create the chance for a significant mid latitude response.
I will post RMM Graphic shortly below.






The AR drums are beating stronger for Central and especially Northern California this AM for the end of the year. This would be a pattern with higher snow levels if it develops.


Beautiful weather can be expected more often than not between today and Christmas Day.  Yesterdays high was in the mid 30s with today reaching the upper 30s. The low this morning was 8 degrees. However, in the colder valleys, lows have been -8 in the community of Crowley Lake -12 in Bridgeport.  As a note, at 11:00am this morning, it was still only 4F degrees at both Crowley Lake and Bridgeport!  Burr!!   In the Community of Lee Vinning at Mono Lake have had nights and mornings of Freezing Fogs. Mono Lake is a salt lake and its waters are open all year!

The Guidence……

We still have an upper high in the Gulf of AK. There is a remaining weak southern stream over the eastern pacific that includes a weak upper low off the CA coast.  That low will kick in tonight and outside of high clouds, no precipitation is expected from it.  The Upper High will develop into a closed Anticyclone toward mid-week next week north of Siberia, eventually sagging south over that area and dissipating after Christmas.  The downstream effects will be a deepening Trof near the dateline and a building and progressive upper ridge over the far eastern pacific. As the Ridge sharpens early next week, a short wave trof slides south through our area bringing the slight chance of some snow showers Tuesday evening. This pattern is associated with a NW Jetstream into the pacific NW.  It will get breezy in Mammoth later Tuesday into Wednesday with a period of wave clouds as well! The upper jet is well NE of us by Wednesday night and Thursday.  By Thursday night, the upstream ridge builds into CA while a short wave trof comes through the upper ridge early Friday. High clouds are certainly possible Thursday and Friday. Thereafter, the upper ridge strengthens Saturday into Christmas Day Sunday. Our warmest daytime temps may reach the low 50s Saturday/Sunday/  Lows at resort levels will rise to the 20s. Its going to be a beautiful holiday weekend!

Week 2:

This is where the pattern Dicey…..

This morning, there are a lot of unknowns about the weather outlook toward New Years. More details will become clearer by Christmas.

This is what were dealing with…..

The new guidance and an increasing number of ensemble members are breaking down the Siberian block toward the middle of the week after Christmas Day. That block keeps the long wave trof near the dateline and the downstream ridge over the west coast. When the block breaks down, it will allow the storminess over the western and central pacific to progress east. Depending upon how strong the west coast ridge remains, that will dictate where this energy will go. Some area of the west coast is going to get Clobbered! I can not say at this time where it is going to happen.  But there is going to be the potential of a Major Atmospheric River associated with it! This is a warmer pattern with higher snow levels.

The most likely area will be the Pacific NW, however some model runs show it into Central and Northern CA between the 27th and the 30th. This mornings GFS deterministic run had a 190 knot upper jet at 250MB extending from just west of Japan all the way to the eastern pacific. Although this pattern does have some limited MJO support, its way way to early to be concerned.


More later next week or sooner…


Dr Howard and the Dweebs…………………….:-)