1-15-2023 830am

Exciting meteorological development with this last significant storm.  The new ICON model 12z run shows the upper level wave with this last system, coming through Sacramento late morning while a surface low is over Monterey Bay at 400am and crosses the Sierra near Mammoth late AM. This will bring a bonus of snowfall to Mammoth Monday with some 3 more feet expected on the mountain. The Snow will be light powder with higher snow to water ratios than past systems this month. 12 or 13:1

I am still expecting another a smaller storm Wednesday night into Thursday with light to moderate amounts. The Euro is in some what agreement. See below…


Saturday night 9:55pm….1-14-2023


Just saw the new 00Z Sunday GFS model run.

Apparently,  this model run wants to dive the following short wave after Tuesday, further west to the Northern CA coast late Wednesday afternoon before progressing it through Central CA Thursday. Previous runs had this as an inside slider with mainly wind and very light snowfall. Well need to see the Euro come into agreement tomorrow and if it does, this new twist brings the possibility of moderate snowfall Wednesday night into Thursday. Preliminary estimates indicates between another 5 to 10 inches of snow if the Euro comes into agreement. Stay tuned….

After a decent break, Friday, Saturday 20th and 21st. into that early Sunday. The next system system drops south from Alberta and British Columbia, Canada. So it’s source region is dry and cold. It heads for Southern Nv and through the process,  can give us cold, windy, showery weather. This for Sunday night and Monday the 22nd and 23rd. Thereafter, as indicated in previous discussion, serious retrogression of the Eastern Pacific high begins to occur.

Sometime during the last week of January, we’re likely to see a major storm for California. I don’t see an AR yet but a strong subtropical tap could occur as the Trof that going to develop shows up as positive tilt and is deep as well.

Comment; while the storminess the past two weeks was not related the MJO forcing, the next storm cycle apparently is.


As of 9:00AM, Mammoth Mt has picked up about 9 to 12 inches of new snowfall since yesterday when the storm began. Another 4 to 5 feet is expected by Tuesday AM. Winter Storm Warnings are hoisted now through Tuesday at 10AM. Since the mountain has received about a foot, up to another 5 feet is expected by Tuesday AM.

Fridays System has passed bringing mainly light to moderate amounts. This current system has the AR attached to it so heavy amounts expected to develop later this morning into the evening. After somewhat of a break Sunday with very light snowfall, the last of this storm cycle will move in Sunday night with strong winds and heavy snowfall though Monday PM. Expect possible white out conditions in the morning.

The Monday/Tuesday system will be the last of the storm cycle. The pattern transits to an inside Slider Type/Great Basin low…Wednesday afternoon into Thursday. This pattern may offer some snow showers with gusty winds over the upper elevations and somewhat colder temps. Highs in Mammoth will be in the mid 20 mid-week. Then improving weather Friday into Saturday before another system Sunday afternoon into Monday dives north south into the Great Basin and desert southwest.  This is a windy pattern over the Sierra Crest and north wind prone areas. Some light snowfall is possible with light amounts if any.

The extended out for the following week shows another cold Great Basin Slider the 25th and 26th bringing the possibility of more upper elevation wind and light snow. The upper air hemispheric pattern is suggesting this morning that retrogression will begin to take place around the 26th. The MJO is strong going into Phase III of the RMM. (See previous post for that comment)   So odds are good that the eastern pacific high backs up again and a new storm cycle will begin just before the end of January.


Highs mid week in the mid 20s lows in the single digits and teens.


Dr Howard and the Dweebs…………….:-)