Winter Storm Warning Hoisted for Mono County for 10:00am Christmas Eve To 4:00am Christmas Day…..1 to 2 Feet Expected….Platinum Powder Alert for Christmas Eve into Christmas Day….MJO Continues on the Move

Christmas Eve:

QPF has been updated to reflect 12 to 24 inch amounts from this Powder Hound by Morning…

Very cold the next 2 days………….

Nice gift under the trees…..

Ho Ho Ho….


Some light snow possible Monday……………Then dry through the end of the year……………..


Wednesday 12/23/19 – 8:30AM Update:

Latest QPF forecast for Yosemite is 1.00.

So on Mammoth Mt at 15:1 that is 15 inches

At 18:1 at 10,000 that is 18 inches…  We’ll see how it works out by Christmas morning…..


There are a couple of small weather systems that may bring a few inches of snow both Monday and again Wednesday. It then goes dry through the end of the year….

MJO and other curiosities…

  1. The SOI has been weakly positive or weakly negative for sometime now….
  2. The MJO is located crossing from phase 5 to phase 6 today.
    a. With the convective portion of the MJO envelope now moving into the Western Pacific…a more upper convergent pattern should emerge north of Australia, allowing the SOI to become negative again. This should provide for stronger westerlies along or near the equator.  So I expect the SOI to possibly turn strongly negative in the next week.
  3. As the MJO shifts further east through the western pacific….the PNA will become strongly positive providing ridging between the far Eastern Pacific to the Western Rockies then north into Canada. This should cut the precip off over the pacific NW and allow them to dry out.
  4. If the ECMWF is correct in progressing the MJO into Phase 8…high amplification of the western ridge will bring the first cold wave into the eastern sections of the country with the 1st good snow over much of  New England.  In that El Nino is strong and the enhanced subtropical jet is as well, I do not expect the cold to last long over the east as it will most likely get flushed out over the Atlantic.
  5. It is what happens next that is important to California. The Composites show that as the MJO progresses well east through Phase 8 that the EAJ extends east to the west coast again…this time under the block to the north. This will be the first opportunity to get an El Nino related storm track into the southern half of the state between the 6th and the 15th of January.

Dr Howard And the Dweebs………………:-)


A nice day is expected Wednesday with gusty winds over the upper elevations. I expect the snow to return by Thursday morning with the winds ramping up again.

12+inches over the upper elevations is expected with 4 to 7 in town.  Christmas Day will be partly cloudy and cold with highs in the teens and some scattered light snow showers possible. I do not see any large storms on the horizon between this weekend and the New Year but there is the chance of some light snow early next week.

MJO: The MJO will be the big story that will really change the pattern over the next 2 weeks. As the inter seasonal system moves from Phase 6 to 8, precipitation will end in the pacific NW, shortly after the new year as a Mega Ridge Builds into the PNA sector. It will be what happens later that will be interesting, as the MJO moves from phase 8 to possibly phase 1.  This is where the Pineapple Express will often times set up.


More later……

Wet Pattern to continue through Tuesday afternoon with very significant precipitation Totals for the west side and sierra crest…..much colder system to quickly move through Christmas Eve……MJO is making all the right moves!

Tuesday: 10:20AM

Mammoth Moutain picked up 2 to 3 feet of wet snow…..

A break Wednesday withy breezy conditions and cooler then a Platinum Powder snowfall Thursday and Thursday Night….


Update at 12:00PM



8:15PM Monday:

Were doing really Well! temperature now 31 degrees at 8200 foot; CRFC just updated with 4.00 of QPF for Yosemite by Tuesday afternoon. The IOP will be from 10:00PM to 4:00Am so bigger snows on the way!. That will be the period of the most intense precip so hang in their baby!

4.00 6:1 = at least 24 inches of cement. But wait!!  The temperature at the summit is 21 degrees!  That’s better much better than 6:1!  One things for sure…the god squad up on the hill will be very busy in the AM.  Just try to sleep-in with the 155 MM Howitzers going off in the morning…..!!!


Platinum Powder alert will be postponed until the late AM. Dweebs want to see 4 more runs….


The Dweeber…………………………………………………


We have had wetter storms than this one, but this is fairly wet.  The nose of the hose hits the sierra tonight into Tuesday morning.  Wet snow will continue in town and not as wet snow will fall on Mammoth Mt.  Actually it is great news for the sierra snow pack as 3 to 5 inches of water is forecasted at snow to water ratios of about 6:1 through Tuesday PM. About 2 feet of sierra cement is expected by Tuesday Evening over the crest.

Winds have been ramping up over the higher elevations, with the freezing level slowly rising as well. The freezing level is expected to peak out at about 8500 Tuesday Midday with a snow level of about 8,000, before falling Tuesday night.  After a break Wednesday, a very cold trof will push through the area causing possible local blizzard conditions. I am expecting 7 to 12 inches of snow from the Christmas Eve storm over the upper elevations….at snow to water ratios of 15:1 to 18:1.  In town, lesser amounts are expected, possibly 4 to 7 inches.  According to the CRFC,  the freezing level is forecasted down to 1500 feet by Friday AM  That’s a snow level of 500 to 0. But of course by then, there will not be much of any snow falling Friday Christmas Day, contrary to earlier forecasts. The system is forecasted to move through….Too fast. Nevertheless, some fine powder will be for the tasting!

Saturday looks Fair into Sunday PM…..


A little MJO never hurts:

If you look at the Classic El Nino forced wet weather pattern for California, it is highlighted by the positive phase of the PNA and an extended low height anomaly between Hawaii and the Gulf of AK.  You have to have anomalous above normal heights at 500MB between Eastern Alaska to Western Canada to act as a block.  The westerlies are thus forced to duck under the block and the hyper extended subtropical jet through Baja, helps the pattern pull through CA.  That has not happened yet…..

Will it?

It is sure beginning to look like it.  So what needs to happen?

  1. We need some MJO in the right place. Like Phase 6 and especially 7.   An interesting reaction happens when the MJO moves out the Indian Ocean toward the western pacific. The PNA flips from Negative to Positive at about 130 East. Heights rise along the west coast and especially over the pacific northwest.
  2. If you want to see why I feel that the PNA is getting ready to flip, look at the MJO forecast by the GFS and its track and then look at the composites for January during an El Nino and see the loading pattern for the teleconnection.
  3. The Forecasted MJO:

a. Phase 6 composite 500MB Heights in January :  

b. Phase 7 Composite 500MB Heights in January:  


Timing?…about the end of the 1st week of January


For you Platinum Powder subscriber’s, a special discussion this evening on the Christmas Eve storm…


Dr Howard and the Dweebs…………………….:-)


Small Storm Now Affecting the Sierra with light snowfall and gusty winds……The current active weather pattern will likely continue though Christmas Day……

Sunday Afternoon…..Low and behold….. It just may be showing up in the longest range of the EC and GFS the pattern that we have been waiting for….End of the first week of January.


Sunday AM:   Mammoth Mountain Reports 6 to 8 inches of new… 

Best ‘Night of Light’s’ Ever at Canyon Lodge Last Night!! With a Fireworks Areal Display that rivaled any July Fourth Celebration… 

Brief update this AM…..

There is quite an unsettled period developing with overall light snowfall expected on the east side of the sierra.  Because of the lack of dynamics and angle of the upper flow to the sierra, the best snowfall will be over the west side of the sierra and up to the Crest. Areas east will have a lot of shadowing…..  A windy pattern will developing as well with a WNW jet that will eventually sag south of Mammoth by Christmas Day. Strong gusty winds are highlighted beginning later today then on and off into Wednesday…..  The Snow level will rise to the 7500 foot level by Tuesday afternoon but come down Wednesday and especially Christmas Eve and Day.

Snowfall amounts in town will be light through Wednesday. With no more than 1 to 5 inches in any 24 hours period. The Christmas Eve storm is likely to bring a foot plus. Wednesday appears to be the best day for travel…And again the following weekend

Because the models are differentiating on the exact track of the Christmas Storm…The Dweebs will fine tune this one early this coming week….


The Eastern Sierra will continue to have unsettled weather with more wind early to mid-week than precipitation. Today ‘s present storm according to California Rivers Forecast Center has the area between Yosemite to Huntington Lake with about .85 hundreds QPF.  At 10:1 that’s about 8.5 inches of snow over the upper elevations.

The next pattern change coming up for next week is associated with a strong WNW jet that will drag a lot of moisture into Northern CA. However, only light to possibly moderate amounts will fall over the Southern Mono County Sierra Crest Sunday night into Tuesday Night. What we have here is a strong WNW upper jet into Northern CA and Oregon.  This is potentially a very windy pattern for the upper elevations, Especially Monday into Tuesday night.  However there will be waves in this upper flow that will bring wet snow to the Sierra.  Note:  If you are planning on Flying to Mammoth early next week, and especially Monday and Tuesday, you may want to have an alternate plan incase the flights are canceled due to strong winds.  Wednesday does not look “as” windy and may be the best break from the upper jet which begins to pivot from the WNW to from WSW Wednesday into Thursday.

Of course there will be periods of precipitation beginning Sunday night on into Tuesday Night. It looks light Sunday night with about .25 of an inch of water EQ and possibly moderate precip Tuesday with amounts around .50. The snow level will be rising and so expect wet snow over the upper elevations with the snow level rising to about 7500 feet by Tuesday afternoon. It begins to come down Tuesday night into Wednesday and drops to 2700 feet by Friday AM. So Friday Christmas Day will be quite cold.

A colder storm is expected Christmas Eve into Christmas Day. That one may bring an 18 to 24 inch storm….Depending upon how quickly it moves in and out.  It is expected to begin sometime between 4:00am and 10:00AM Thursday with heavy snow Thursday afternoon and snow showers Friday…..Saturday looks Blue Birdy.


More later…..


Dr Howard and the Dweebs……………….:-)