Next big storm has moved into the high country with moderate snowfall…..Cold Air trapped in the lower elevations will ensure snowfall well into the afternoon….Rain still forecasted for later tonight through Sunday Night with rain changing back to snow Monday Morning in Mammoth Lakes….

Saturday at 1:30 PM

Here are some interesting temps to show warm frontal snowfall. It will give you a profile of temperatures;

Temps:

Summit of Mammoth Mt  25f
Main Lodge                       30
Village at Mammoth          26
Crestview station               25
Mammoth AP                    25  Moderate Snow
Bishop AP                          31  Light Snow

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The Temperature at Mammoth Lakes this morning has been about 20 degrees and so precipitation is warm front like induced, as warm moist air is being lifted by both the sierra and cold air at the surface. Snowfall will continue and be moderate until the winds pick up later today and mixes it out… Snow may accumulate over a foot in town before it changes to rain.

I just has a look at the Pine flat Dam FMCW S-Band Snow Level Radar. It is currently indicating that the snow level due west of us in the sierra foothills is 9300 feet. So we are trapped in the cold air in the Great Basin side of the Sierra and it is isothermal down to at least the Crestview Station.

When will the snow change to rain? Sometime this afternoon. Possibly as late at 4:00PM. However, there is no certainty in a forecast like that.  Once the winds pick up the snow level will jump very quickly!

After the rain event Sunday and Sunday night, the snow level will come back into town sometime early to mid Monday Morning…..

The Town of Mammoth will receive several feet of snow next week…..

Outlook….

I will have a detailed outlook in my weather letter put together tonight for Monday AM….

Just a hint though shows the storm track lifting north Friday into the weekend….

 

Dr Howard and the Dweebs………………..:-)

Let the Weather Patterns Begin!….Cold Storm 1st Mid Week then Wet and Wild over the weekend……General Quantitative Central Sierra precipitation forecasts of 25 to 30 inches of water EQ by January 13th……

Thursday AM Update:

Think we have had a big winter so far?  Think again…According to the DWP, as of January 4th yesterday, Mammoth Pass was only 101% of normal. However, that does not reflect much of the 7.85 inches that has fallen by 10:00AM Thursday….

 

  1. Mammoth Mt Reporting 3.5 feet to 7 feet of new snow storm total so far….Another 3 to 7 inches is possible today.
  2. At Mammoth WX .com 34 inches of snow has fallen.
  3. Mammoth Pass as of 8:45 AM Thursday, has a storm total of 7.84 inches
  4. Major flood event is forecasted for Yosemite Valley Sunday Afternoon
  5. AR event to begin as snow Saturday morning with snow changing to rain during the late afternoon or evening. Heavy rain is expected by Saturday night with the snow level at 9000 to 9500 feet into Sunday AM
  6. The Snow level will remain above 9000 feet until about mid afternoon Sunday. It begins to come down about 4:00PM Sunday then lower throughout the night and into Monday.

Here are the updated freezing levels for Yosemite from California Rivers Forecast Center (CNRFC)

  1. Sunday  4:00AM    10,000 feet
  2. Sunday 10:00AM     9700  feet
  3. Sunday   4:00PM      8900 feet
  4. Sunday 10:00PM      8600 feet  (Snow sticking at Canyon Lodge then Eastward to the Village at Mammoth over night)
  5. Monday  4:00AM     7900 feet   (Snow sticking in TOML)
  6. Monday 10:00AM    7300 feet   (Snow sticking on Highway 395

Note:   The snow level is 500 feet below the freezing level in a saturated air mass; These freezing level are provided by CRFC.

The Water EQ is still the same; about 10 to 12 inches over the Central Sierra through the weekend and between 6 and 7 inches in the Town of Mammoth. The good news this morning is that the very latest freezing level information from CRFC, for Yosemite, which I use as a guide for Mammoth Lakes is showing that colder air will be moving into our area sooner, like Sunday night into Monday AM.  For those that are interested, compare the freezing level info below in Tuesday afternoons update to what you see above. As you can see, by Monday 4:00AM, the freezing level is some 1200 feet lower!

Outlook:

AR = Atmospheric River  SEE:    https://www.esrl.noaa.gov/psd/atmrivers/

The latest “updated” QPF (Quantitative Precipitation Forecast) for the Central Sierra between 4:00AM today Thursday, through Friday night at 10:00PM the 13th of January is 30.00 inches of Water.

 

AR #2 arrives Saturday AM with a break Monday Night and Tuesday

AR #3 is a smaller AR and the Dweebs believe that Mono County will just get a lot of Snow above 6000 feet.

AR #4 arrives Thursday Afternoon the 12th. This too looks to be a colder storm with it winding down late Friday into Saturday the 14th.

I will have a special update on the longer range this weekend via my Weather Letter….

Dr Howard and the Dweebs………………….:-)

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Wednesday Jan 4th:

1st in a possible series of 3 AR events is unloading on the Mammoth Lakes 24 hour amounts 2.23 inches of water and 27 inches of new snowfall at Main Lodge. There is about 18 inches at the Village at Mammoth.

We are about 1/2 way through this storm…

2nd Atmospheric River will hit Saturday with the peak late Sunday AM. Snow level possibly going up as high as 9500 feet by 10:00AM Sunday. Snow level will come down late Sunday afternoon into Monday.

3rd Atmospheric River may occur next Wednesday through the following Thursday Night. This appears to be the last in the series…The wet pattern ends when the blocking over AK and the Bering Sea ends….which is about Friday the 13th of January…

Your lucky day….the Dweebs still see a total of 25 to 30 inches of Water over the Central Sierra from this storm cycle which began yesterday the 3rd and will likely end by Friday the 13th……

 

 

 

Tuesday 1:45 PM Update:

 

7 day QPF posted by WPC covering period through Tuesday night next week is 22.8 inches.  This does not cover the storm for Tuesday night through the following Friday,  which may be the last in the series….

There is chat about the rain on Sunday.  Here are the freezing levels just released by RFC

 

Here is the latest freezing levels for Yosemite for the subject time frame.

  1. 4:00PM Saturday      8800
  2. 10:00PM Saturday    9300
  3. 4:am Sunday            9500
  4. 10:00AM Sunday   10000
  5. 4:00PM Sunday       9600
  6. 10:00PM Sunday     9200
  7. 4:00AM Monday     8500

Note;  in a storm like this the snow level is usually 500 feet below the freezing level.  (saturated air mass)

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The first in a series of wet storms will hit the sierra beginning today with 36 hours snowfall forecasts in the 4 to 5 foot range for Mammoth Mt and 2 feet plus at the 8000 foot level for Mammoth Lakes. There is a small Atmospheric River taking place tomorrow Wednesday. The Cold Air currently in place will gradually get flushed out over the next 24 to 36 hours. The set up is cold troughing in the pacific NW coupling with a WSW mid latitude upper jet undercutting the GOAK Ridge. This is associated with Gulf of AK Blocking pattern #1. (-EPO); Pattern #2 will be associated with the same ridge that will retrograde (back up) to the Bering Sea. The teleconnection is called the (-WPO) This pattern is warmer and wetter because with the new location of the upper ridge, and energy coming over the top of the ridge will dig a new long wave Trof, both further west and deeper into the Eastern Pacific. It just so happens that there is a mid latitude subtropical low NNE of Hawaii that will be picked up Saturday and Sunday. This coupling of this action picks up the AR and pulls it onto CA Sunday. This AR is a large one and broad. It is a two-day event. It will have precipitation rates of 1 to 2 inches of QPF  every 6 hour period for over 24 hours.  Last nights WPC 7Day QPF  showed 25 inches over the Central Sierra near Mammoth. That does not cover the end of this storm cycle.

 

If you want to know if the end is in sight, you have to know when the block will be gone from the Bering Sea. It looks like it will weaken by the end of next week.  So if that is true, about the 15th or so should  be the end of this pattern. If the blocking persists with any significance, the pattern will continue wet until which time the block either falls apart or it retrogrades west over Siberia, Rus.

Although this WX Patten will be an inconvenience to many, it will be fabulous for the forest and the reservoirs through out the state. It will put a huge dent in our drought!    Watch for Alaskan blocking to most likely return in February as well…..

 

Dr Howard and the Dweebs………………….:-)

Major Storm Cycle Ahead as -EPO Rex Block Forces Strong Southerly Stream into Central West Coast….Copious AR Precipatation Event Probable for the Northern and Central Sierra….

UPDATE 10:45 AM Monday:

The QPF updates keep coming and the resounding questions becomes… will there be a break as several waves of energy are expected to pound Central CA this week.

The series QPF 24 hour bull’s-eyes moves slightly north and south of a pivot point from about Mammoth Pass this week as follows..

  1. Day 1   24 hour amounts  4:00PM Monday to 4:00PM Tuesday      =              .35 to .50
  2. Day 2   24 hour amounts  4.00PM Tuesday to 4:00PM Wednesday =                 4.11
  3. Day 3   24 hour amounts  4:00PM Wednesday to 4:pm Thursday    =                 2.50
  4. Day 4   24 hour amounts  4:00PM Thursday     to  4PM Saturday     =                 2.50
  5. Total day 5 MAX   About 9.5  inches at Mammoth Pass Before Snow levels rise to 9000 ft  This means that the town may get 3 to 4+ feet before AR event.
  6. Total 7 day Max 18 inches over Mammoth Pass

Note:  This has the potential to be one of the historically significant precip events for Central CA.  Considering all the fires the past 5 years, leaving burn scars in the forest.  Rock slides, mud flows, and road damage on the west side of the sierra are being considered….

On the bright side, most if not all reservoirs will be topped out by the end of this storm cycle.  Some Dams may be forced to spill….

PS  I looked at both todays 12Z Monday GFS and ECMWF total 10 day QPF. added them together and averaged them out. They paint about 30 inches of water over a 10 day period at MAX over the Sierra.

 

 

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Monday the 2nd 8:40am update shows that the 1st storm moving in Tuesday afternoon will continue through Thursday morning with snow showers Thursday afternoon into Friday. The storm will drop between 18 and 24 inches of snow in town and about 3 feet on Mammoth Mt.

The big AR event for the upcoming weekend will begin Saturday in town. However, preliminary guidance indicates that the freezing level goes up to 9300 feet Saturday night the 7th.   At this time….Odds are higher that the weekend storm will begin as snow, turn to rain in town Saturday night and into Sunday….then turn back to snow late Sunday night…..  The snow level may rise as high as 9500 by Sunday 12:00PM. This of course is all subject to change…..but confidence is pretty high that a major Atmospheric River Event will hit next weekend……7 day QPF is between 16 and 17 inches over the Sierra Crest near Mammoth Lakes by next Monday AM. The Dweebs expect this forecast may even be under done….  Stay tuned for updates….here and in my weather letter….

 

The Dweeber……………………:-)

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The Dweebs have been watching the global models and their handling of a weather pattern that has already happened before in early December and has been destined to repeat itself again now for January. It appears that the current Arctic front will stall itself out, mostly north of 40N and give way to a strong under cutting, subtropical jet which will eventually couple with the polar jet later this week.  The trend of ensembles are nothing less exciting than the event itself which may deliver some 5 to 8 feet of snow to the Town of Mammoth, (If it is all snow) and some 12 to 16 feet over the upper elevations of Mammoth MT over the next 7 days. We will have two Atmospheric River events, one light to moderate one mid week and the other AR event will hit Saturday into the following Monday. Folks…that one will really get your attention! So pineapple up and ever,

This is a developing pattern with the forecast ability of the details likely only within a 24 to 48 hour period before each surge….The Crescendo is likely over the upcoming weekend into the following week….

Get the shovels ready and the snow blowers fired up and working….We should have a wild 7 days ahead,  beginning soon….

 

More later……………..

 

Dr Howard and the Dweebs…………………………..:-)