Colder Weather with drier than normal conditions will be the rule through the 27th…Retrogression in the long wave pattern still favors more snowfall first week of February….

North West Slider to drop another 3 to 5 inches Wednesday night and another 2 inches Thursday

Snow to water ratios will be 15:1 or greater so “Platinum Powder” snow>>>>Then fair dry weekend into next week…

With the exit of the Trof that brought wind, moderate snowfall Sunday night into Monday AM, much improved weather will highlight our resort the next 8 to 14 days. Our hemispheric pattern is showing up more La Nina like as it should. With the Long Wave Trof developing over the Inter Mountain West while the mean ridge position is some 700 -1000 miles west of the Sierra off shore. Expect mainly inside sliders type systems. These will dominate our weather, bringing small shots of powdery snowfall and much colder weather. High temperatures will be mainly in the 20s now for Mammoth this week with nights in the Single Digit’s or possibly below zero Thursday morning. Thursday AM will be particularly cold for Mono County’s high elevations valleys. Places like Bridgeport and Long Valley may go -20F to -30F that morning!


Tropical Forcing:

The CPC this morning made a point to say that the MJO is Destructively Interfering with La Nina. At the same time, the scientists are saying that sub surface cooling is occurring over the equatorial central pacific, which may delay ENSO neutral conditions to develop this spring.

The pattern we just came through was more akin to EL Nino forced west coast weather. So far, climatologist’s have not come up with an agreed upon answer.

A return to more La Nina like forcing is what is expected through Months End.  So it looks fairly dry with only few small cold systems.

The climatic prediction center also indicated its week 3 outlook is for retrogression of the Eastern Pacific high, back toward the Central Pacific. This retrogression may begin the end of January, and complete during the first week of February. Rain and snow should return to California during the first week of February.  This pattern is not expected to be a return to what we just went through with several AR’s  Rather, a more typical return to mid winter’s La Nina pattern, with cold storms and the focus of the most anomalous precipitation back over the Pacific Northwest.


BTW; Mammoth Mt has indicated that the season total at the Main lodge is now 378 inches.  What a difference a year makes!


More Later….


Dr Howard and the Dweebs………………:-)

Winter Storm Warning in Effect….Expiring at 10:00PM Tonight……White Out Conditions now in town with Gusts to 30MPH…..Snowfall will taper off later today……Tuesday will be dry……Light Snowfall expected Wednesday night and Thursday AM then dry Friday Saturday Sunday…

Surface Low crossed the Sierra this morning and is located about Hawthorne, Nevada. Nice deformation zone set up between Hawthorne, NV and up into Reno providing snowfall over Western NV and the Eastern Slopes of the Sierra. SW flow has increased in Mammoth with whiteout conditions at this time. Please do not drive under these conditions… Please check with Caltrans before traveling north or south on Highway 395. Mammoth Mt shows over 4 feet storm total over the past few days….Up to another foot is possible today…. Platinum Powder Alert for Tuesday from todays storm with one foot or better on the slope at 15:1 (Platinum Powder)…

Weather Discussion:

Latest Model Simulations show Snowfall rapidly tapering off after mid afternoon and will end by early evening.    After the break in the snowfall later today, It will be quite cold Tuesday with diminishing clouds then clearing over night Tuesday night. Low temps will will go -17F to -6F throughout Mono County early Wednesday morning and although the Blue Birds are gone, it will be that kind of day!. Cold Dry Powder a sure bet with EGO snow! Make sure you have the right wax for the very cold snow in the morning…

Another weaker system will bring some 1 to 5 inches Wednesday night into Thursday AM with high snow to water ratios. That will be the last storm in this cycle. Temps will remain cold for the rest of the week with some moderation over the weekend. 20s for highs.

Looking at next weeks weather….Over all great!  There is a cold system that drops out of BC, Canada bringing very cold air and NE wind over the Sierra Crest Monday the 23rd. Its to soon to see if we get any meaningful upslopes from it but it is not expected to bring any substantial snow…..Mainly snow showers Monday. Today’s model simulations show the wind with this pattern at 700MB (10,000 feet) is strongest over the Northern Sierra. The system spends time over Tonopah, NV, during early morning hours Monday…..Best chance for upslope.

Thereafter, there will be some windy periods week two but northing unusual and it looks like precipitation will be below normal.

Tropical Forcing:

There are a few very interesting developments the last week of this month.

The first strong MJO; Madden Julian Oscillation is expected to affect the mid latitude flow toward the end of the month. Retrogression is being shown in the global models the last week of the month of January. Another storm cycle is now a good possibility as the MJO is forecasted to be very strong in the RMM Phase 3. Composites show wet weather for CA in January and February for that phase.

Although a new long wave Trough is expected to carve out over the far Eastern Pacific toward months end, we do not know if this pattern will set up with AR’s again.  However, today extended model 12z GFS simulations for early February shows that; so there is some possibility although that pretty far out in time. Therefore please consider your snowpack around your home and or businesses and diminish the loading on your roofs. Do this before the end of the month!! The last series of ARs were not really warm AR’s. They were not the Colloquial Pineapple Connection as the moisture was mainly subtropical. Should an intense static AR develop from Hawaii, with freezing levels well above 10,000 feet, that could be disastrously.  While there is no forecast for that that at this time, it is still a good idea to have roofs shoveled in the meantime.

See one possibility below:



I also wanted to add that there is a very strong Strato-Warming event taking place over the Arctic in a few weeks. See graphic Below.   That will most likely have an affect on our Northern Hemispheric Pattern. However, it is unknown to what change it will bring.



Stay in touch with Mammoth’s best weather site!! Reporting the Weather in Mammoth for the media for over 40 years!


Dr Howard and the Dweebs…………………:-)


Winter storm warning is still Hoisted for Mono County through Tuesday AM….Another smaller storm hits Wednesday night….Then a break Friday and Saturday……


Platinum Powder Alert Tuesday!…


Latest model simulations begin the snowfall in Mammoth toward Midnight tonight. Still Expecting up to 3 feet on Mammoth Mountain by Tuesday. Between 18 to 24 inches in town. The snow to water ratios will be much higher with this storm between 12 and 15:1. A Platinum Powder alert is hoisted by the Dweebs for Tuesday for at least a foot of powder at 15:1 in the upper bowls of Mammoth Mountain.  Please take your snorkels with you.

Expect improving conditions Tuesday Afternoon into Wednesday. Another cold storm is expected late Wednesday night into Thursday. Another 7 to 10 inches is possible on the mountain and 5 to 7 inches in town.

The Dweebs are expecting improving weather late morning Thursday with just some light lingering snow showers durning the afternoon.  It will be another dry powder day Thursday.  The further outlook looks dry Friday through Monday.