Archive for January, 2023

1/7/2023

10:40AM

Quick update:

No change in the forecast for today. Flat light conditions, no significant snow today. Winds picking up over the upper elevations.

Next wave comes in tonight with light to moderate snowfall.  Expect about 6 to 12 inches over the upper elevations by mid day Sunday. About 3 to 6  inches in town. Wave should be through with diminishing winds aloft early Sunday afternoon. Decent travel in the afternoon. High today 35 low 25.  High on Sunday 35…

Next storm is the wet AR for Monday.  Moist surge moves on shore about mid night Sunday night and increases early Monday AM. Snowfall rates increase Monday AM after midnight Sunday.  I have questions in regards to the snow level Monday afternoon as the freezing level goes up to 8000 to 8500 feet near Yosemite. The Snow level forecasted by NWS is at 7000 feet.  Possibly the AR does not get that saturated air this far east?  Will update snow levels tomorrow afternoon for Monday.  FYI;  California Nevada Forecast Center (CNFRC) is forecasting shows that during the AR and including the cooler part of the storm Tuesday, Yosemite gets 6.62 inches of water and Huntington Lake gets 7.15 inches of water. That’s about that 4 to 5 foot storm for the upper elevations for that storm. Add on the Sunday system for about a foot…..5 to 6 more feet!

Outlook:

For the outdoor enthusiasts,

It is estimated that a break in the weather may occur mid-day Wednesday through possibly Friday with Sun, periods of wind and mainly periods of very light snowfall.

Longer Range;   (Outlook, highly subject to change)

The pattern is beginning to change a bit later next week in that pressures aloft are increasing over the Rockies. This will slow the advance of weather systems later next week as well as weaken a few including the Friday night system into Saturday night. 14th and 15th.

Beyond that weekend the storm track is shifting more to the north, and so snowfall will be less with each storm, beginning around the 18th of January. Again, this is subject to change…  (See Day 8 Means below) See Split Flow Day 8.

Dr Howard and the Dweebs…………………….:-)

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Beautiful Blue Bird Day!   Weak ridge of high pressure that moved in last night will be with us today and ensure a wonder day for Skiing and Boarding.  Mammoth Mt now Boasts 11 to 15 foot base. 37 inches of new fell over the past 3 days.

Weather pattern continues active with a small system for Saturday, bringing an inch or two of snow and moderate wind.  Winter storm warning are hoisted beginning Saturday at 4:00AM mainly for wind. The tempo for snowfall will increase Saturday night and especially Sunday as a moderate storm moves into the area for Sunday. The NEXT STORM is a powerhouse.  It contains a strong atmospheric river (see Graphic’s below), beginning Monday morning through Monday night. Copious amounts of precipitation are expected to fall with the snow level rising to 8000 feet Monday.  3 day Snowfall amounts will be in the 4 to 7 foot range over the higher elevations Sunday through Wednesday AM. There looks to be a break Wednesday into Thursday.  Another storm is possible late Thursday through Friday.

As a note, there are several surface lows rotating counter clockwise around the mother low early next week. However, there are two surface lows that make it onshore early Monday Evening and another later Tuesday AM of significance!

2:20 PM 1-2-23

Here are some estimates of timing, based upon the latest Europeans Model Ensemble from this morning;

1. Minor fast moving system now on the coast will bring mainly light amounts of snowfall mainly late this afternoon up until midnight tonight. 5 to 7 inches is possible on the Mountain and 3 to 4 inches in town.
2. There will be a break on Tuesday.
3.  Next system has a level 3 AR, however, will be cold enough for snow in town Wednesday through late Thursday. Looking at a solid 2 to 3+ feet on the mountain with close 18 to 24 inches in the Village at Mammoth.
4. Friday looks dry
5. Blend of models suggest another 6 to 8 feet of snow by next Tuesday the 10th, over the upper elevations.

Outlook (subject to change)

1. Saturday looks dry until the night
2. Saturday night through Monday evening  6 to 12 inches..
3. Tuesday heavy snow developing into Wednesday. (10th and 11th)
4. Dry Thursday the 12th.
5. Major Storm (possible) Friday the 13th

To clear the air.  Most if not all forecasters busted on the snow level last Saturday AM.  Why?  They were all just looking at 700MB temps and most likely 1000mb-500MB thicknesses.

What happened….

A surface low moved in from Sacramento to Reno NV Saturday AM, creating SE flow and convergence on the lee side.  Microphysical processes set up and it virtually stayed below freezing from the dendritic growth zone to the 850mb Surface even though the freezing level was forecasted above 8K  Watch out as this may happen again in the near future. Reno picked up some 8 inches and foot hill communities between 20 and 30 inches!!  Everyone thought that a good part of it all was going to be rain over the lower elevations 🙂

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For the most part regionally, its been quite the past week hydrologically with observed precipitation amounts on the west side of the Sierra between 10 and 15 inches according to The California Rivers Forecast Center.  For the most part, it has been high elevation snow and lots of rain at elevations below 8000 to 9000 feet during the wet ARs. The colder part of the storm yesterday dumped between 3.5 and 4 feet at and above 9000 feet with the likely hood of much more over the upper bowls of Mammoth Mt.

We are now going into a colder phase of the pattern, as although we do have at least one more AR Wednesday night and Thursday. Snow to water ratio’s will be much higher. And….with a larger storm Wednesday through Thursday, several feet of snowfall is expected in the Towns of Mammoth and June this new week.  Its even possible that a Platinum Powder alert will be declared by the Dweebs Tuesday night for the Thursday system. This system looks to meet the criteria of a foot or better at 15:1 on Thursday in the colder portion of the storm, as that system has a -28C Core at 500mb, and 700MB temps -6 to -7 Thursday afternoon. Additionally, there appears to be plenty of precipitation in that part of the storm as well. BTW; We do have a smaller system tomorrow evening. It should be all snow at resort levels Monday evening into Tuesday with lighter amounts possible. .

Outlook;

It appears that there will be several weather systems moving through the high country beginning later Monday afternoon with little break through mid-week. As mentioned above, the main snow event hits Wednesday through Thursday. Thursday’s colder portion of the storm should allow plenty of Fluffy Snow in the colder air during the afternoon!

There will be a few other light to moderate systems the following weekend that are not as cold as the Thursday’s storm. With others possible the following week?

With that last statement said, there is forecasted by the GFS to be a significant strato-warming event that will be taking place beginning next weekend into the following week. This is when temperatures can build in the stratosphere, and possibly displacing or splitting the Polar Vortex. In the latter case, our hemispheric pattern would be affected.  The Main Point is that week two outlooks due to this event are most likely not reliable now. More later in this Dweeb Report as the models adjust to an upcoming change in the pattern over the pacific the following week.

Dr Howard and the Dweebs……………..:-)