Archive for December, 2019

Happy New Year from the Dweebs!!!….End of Year Forecast and Long Range Ahead!!……………………………

Short Term,

Most the of the short term is about wind and milder temperatures….

The Dweebs believe that the Arctic Oscillation in its positive phase will tend to keep most Arctic Air bottled up well to our north. As a result, our wet storms of late November and cold storms of mid to late December will take a back seat until high latitude blocking in the right places sets up.

The short term forecast for the next few days, shows diminishing winds today following by a NW jet diving into the Great Basin New Years Day Wednesday. So today is a good break between the winds and the up-slope cloudiness of Monday with a Sunny Warmer day  and diminishing winds.  Highs today will be in the 40s in town and 30s on the mountain.   Get up there today and carve it up!

A Great Basin Slider will crank the winds up on Mammoth Mt for a few days, beginning on New Years Day into Thursday.  NW winds over the upper elevation will crank up into the 70-80 MPH range over the crest by the afternoon Wednesday with lower elevations in the 40 mph range. Temps will be in the 30s and 40s.  Friday AM looks to be a windless morning…

For the Weekend Outlook, Expect Light Winds Friday AM with Winds strong enough Friday night for some silky wind pack Saturday AM. Winds Saturday and Sunday will be moderate over the upper elevations.  Sunday’s breezes could be lighter than Saturday.   At the moment, the weather system for the weekend does not look to bring any significant chances of precipitation to the high country. It will be cooler over the weekend.   As we begin the new week,  expect lighter winds Monday into Tuesday with Blue Bird Conditions.

Some increase in wind is expected toward the 9th……

Long Range:

As we approach the middle of the month, the GFS Ensemble Mean shows the long wave Trof over the Western Mid-West trending to retrograde westward again. So between the 10th and the 15th the weather will be turning colder again and more unsettled with colder storms.

Its been a long time since the Pacific has opened up with long fetch storms that are wet in nature. The Euro, both in its weeklies and ensembles are showing a period between the 20th and 30th of January with a strong -EPO teleconnection early in that period that ends up with a strong  -WPO toward the end of the month of January. This suggests strong high pressure blocking over the AK to the Bering Sea region by the end of that period with significant under-cutting of the westerlies into the west coast during that time period. That highly suggests the potential for a few AR episodes during that time period.


The Dweebs will keep a weary eye on the developments this January…..


Happy New Year to all…

I wish you all the very best for the beginning of the new roaring 20s!! 

This new year will mark 40 years of providing weather to the Eastern Sierra

Dr Howard and the Dweebs………………….





Weak…..Fast moving Closed Low to bring light amounts of Snowfall to the Eastern Sierra this afternoon into Monday….Low is tracking further off shore which will impact snow fall amounts……Arctic Air retreats to the north as AO goes increasing positive….This will be the last storm of 2019….First week of January looks dry……

12/30 7:50AM


Partly Cloudy today with a chance of light snow showers.  Very light if any accumulations today….


Mammoth Mt reports 1 to 2 inches of new snow over night..


Our weather system was just too weak and too of shore to do us any good…

Expecting a dry week ahead….With clouds and wind at times..


The Dweeber….


Here is an update from the Dweeb Report on the forecast for the small year end storm that is expected to bring up some 2 to 6 inches of snow to the high country over the next 36 hours…


Here are the bullet points that shape our snowfall estimates….


  1. The weather system, a small closed low, will track a bit further off shore.
  2. The system will track well south of of Southern California and turn east near the Cedro’s Islands off the coast of Baja.
  3. The speed is a bit quicker in that is will not slow as much as it approaches the CA/Mex Border.


All considered, the front or main area of Upper Divergence is only expected to bring some .20 inches of precip over the crest. 1 to 3 inches of snow…….The upslope portion for the high country is weaker because the low is further off shore with only some 1 to 3 inches expected through Monday evening.

So the snowfall that is just beginning in Mammoth will end Monday evening. Amounts are expected to tally some 2 to 6 inches between the top of Mammoth Mt to the lowest elevations of the Town.


The Medium Range is shaped by the teleconnection of the Arctic Oscillation going strongly positive. This causes more low pressure to become bottled up over the Arctic and Canada, so that jet stream migrates to the north, especially in the far west like CA.

This is expected to be temporary, as the AO teleconnection will trend negative later week 2 and open up the gates to more storminess out west. Even with the upper jet to our north next week, we will not be without interesting weather. I expect some windy weather later in the first week January. The progs show a NW jet to the north of us….

As the AO becomes negative again toward the 8th of January, along with other teleconnections,  support more storminess out west. The EPO becomes significant, as the negative phase of the EPO will trend to drive the upper jet south again into CA. by a blocking pattern. This looks to be robust pattern change, one that could be quite stormy with a lot of snow in the high country. It looks to be a cold pattern with insider slider systems diving into Great Basin, not real good snow producers for the Central Sierra, better for the Rockies…..The pattern shows colder weather ahead as well with gusty winds…Note, this is a wet jet that may affect the northern sierra this weekend, but iffy at best at the moment.  It would have higher snow levels and strong winds


The MJO:


O’ Boy!  There are so many interference’s coming about with the MJO in the weeks ahead. Tropical Storms….Easterly Rossby Waves, a significant westward moving Kelvin Wave, and of course the on-going low frequency -IOD.  It should be an interesting update from the CPC, New Years Eve!!

PS, it has been a long time with out a significant El Nino…


Another update around New Years Day…



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









Cold Weather to persist through Christmas and the day after with Snow showers….Milder Temps over the weekend…Then some more snow shower expected Monday the 30th…No Major Storminess through the New Years day…..

12-25-2019 Update 9:45PM

A cold upper low was located west of Paso Robles at this time and will slowly making its way south down the coast. The Eastern Sierra near Mammoth Lakes will experience some light snowfall tonight into the morning hours. Amounts will be light., 1 to 3 inches.

However, the Owens Valley is expected to be hit hard with snowfall overnight and throughout the day on Thursday. Winter Weather Advisories are hoisted by the National Weather Service  beginning at 10:00PM tonight through Thursday at 10:00PM.  the forecast from the National Weather service is calling for 1 to 3 inches over night and 2 to 4 inches Thursday….  Travel is expected to be difficult.  If your heading south on 395 Thursday AM, be sure to check road conditions and carry chains.



Mammoth Mt Picked up some 17 inches of snow from the last storm system. Now cold snow showery weather to persist through the 26th.  Short wave ridging will answer the call for some fine fair weather both Friday and Saturday.

The chances of a major storm over the next week or two is not high as the AO (Arctic Oscillation) goes into to its positive phase. That effectively keeps Arctic Air bottled up well up into Canada and Alaska. There is some sign that the AO will weaken and go neutral  during the 2nd week of January.

You may notice that our latest series of storms have split south with most of the energy going into Southern CA  and Northern Baja. Our snowfall from the last system brought about a foot over Mammoth Mt with another 5 to 7 inches on Monday. The 5 to 7 inches was from upslope as cyclonic flow moved east to the south of us.  This pattern was for told in my October 22nd post as I analyzed the CPC Winter Forecast.  SEE: