Variable Spring Weather to continue another 6 to 10 days with Sun and Snow…..Tomorrow Wednesday is one of nicest days ahead….

A highly amplified upper ridge continues full latitude into the Gulf of AK this week.  Upper flow today and tomorrow is right out of the north.  Tomorrow, some of that ridge will spread higher heights into California for about 10F degrees of warming while a small upper low comes through the ridge and down the west coast Thursday. Another short wave seems to track in tandem but is not connected as it moves through the Great Basin and Rockies.

The idea is one more of instability for our area Thursday evening and especially Friday, as if this were winter, this little feature would not do much more than create a wind shift. So it is Mid April and CAPE is running higher now. I expect a few isolated showers Thursday late afternoon and especially the evening over Eastern CA as an area of deformation develops over night. On Friday, a zone of east-west deformation develops across South Central Nevada and spreads further west into Eastern CA Friday, triggering snow showers and possible thunder snow.   As the petite upper feature gets closer to the California Coast and comes through Friday, weak upper divergence is possible, to spread showers up the Sierra. The deformation to the SE should keep some action going into Friday night, especially for the Owens Valley.

Snow showers and a few Thunder Storms with some grapple is possible for Eastern CA late Thursday afternoon and evening. Nocturnal storms may continue well into the evening…..Then additional instability expected Friday for greater Arial Coverage.


Saturday looks to be a fair to partly cloudy day with a little warning.  Antecedent moisture will be left behind for Sundays storm.  The Sunday afternoon through mainly Monday system looks more impressive for the Sierra.. Although not a major storm by any means….This undercutting system that moves in Sunday has decent on shore flow Sunday night into early Tuesday. Just a WAG….this might bring some six inches+ of snowfall to the higher elevations by Tuesday. However, this is just based upon pattern recognition….


High temps this week will fluctuate between the mid 50s Wednesday to back down into the 40s this weekend. Lows at night in the 20s for the most part.


This is likely to be more unsettled WX before the end of the month……


Dr Howard and the Dweebs………:-)

Active Weather pattern to return this weekend with moderate to heavy snow possible Sunday and Monday…..Improving Weather by Mid Week..Then AR Lurking in GFS around the 12th while The EC is dry…..

10:10AM Monday


Mammoth Pass had 24 hour amounts of 3.64 inches.  At 10:1 that’s about 3 feet.

Mammoth Mt Should have between 3 and 3.5 feet total for the second storm.

Town of Mammoth averaged 21 inches

Storm now will favor Southern Sierra, Owens valley and Southern CA.


At 500MB the Upper low at 10:00am was west between Monterrey Bay and SFO.  There is southerly flow is over the Sierra Crest of Southern Mono County and the Owens Valley with SW flow over Southern CA. Upper flow becomes  more SE Tuesday which is more favorable for the Owens Valley for rainfall.

As low makes its move toward the Oceanside, the upper flow is progged to become ENE over Southern Mono County, East side up-slope precipitation is possible for Mammoth Lakes, Tuesday night into Wednesday as convective bands rotate around the upper low.  As upper low moves onshore about 5:00AM Wednesday, easterly flow and upslope continues the possibility of snow showers and isolated thundershowers Wednesday afternoon and evening. By 8:00PM Wednesday evening, Upper low crosses the CA /AZ border near Needles; wrap around continues over the Eastern Slopes of the Sierra for a continuing chance of mainly light SN showers into Thursday AM.


Weekend Outlook:

High pressure aloft builds just off shore for a warm weekend with brief but high snow melt rates….  Highs in Mammoth in the Mid 50s and mid to upper 70s in the Owens Valley by Saturday and Sunday.

Further Outlook shows retrogression and amplification of the Eastern Pacific High to about 135 to 140 West. This will allow both cooling and moderate wind to develop for the upper elevations as these weak short waves travel SSE through the Great Basin.

There short waves are dry but there is an upper level weakness that develops off the Central CA coast that may kick off some showers going into the following weekend…




1:05AM Monday


Weather front has stalled over MONO COUNTY to the north of Mammoth and is pivoting. while the upper low heads south. Heavy snowfall should begin to taper off toward Sunrise. In the Town of Mammoth, 16 inches has fallen as of 1:00AM and so The Dweebs have increased snowfall estimates to close to, 2 feet in town, the very upper limit of the earlier forecast.  Snowfall amounts on the mountain have already totaled about 2 feet at the Main Lodge and so the 2 to 3 foot forecast seems in the bag now….


Once the front is through, steady snowfall will become more showery in natures, the rest of the day…


Sunday 3:55PM

WSW in effect for the Mammoth Lakes

Heavy snowfall to continue through tonight and Monday Morning. Between 10 and 20 inches possible in town and up to 3 feet over the higher elevations….

Snowfall rates to be highest tonight into Early Monday AM.  Since 1:00AM this morning the high was 31 degrees and at 3:30PM it was 27 degrees.   Winds are starting to pick up with some whiteouts occurring…


As far as the Meteorology…


Upper low was located 550 Miles west of Highway 80/Truckee early this afternoon. The low will sag south to just west of the Bay area by about 2:00AM Monday AM. Currently, there is a deep plume of moisture ahead of the low into the Sierra bringing heavy snowfall.   The combination of the storms slow moment and moisture plume will continue winter storm conditions into the Sierra through Monday AM. Snowfall rates of 2 to 3 inches an hour are possible tonight.


The Dweeber……



April 3rd; 10:30AM


Confidence continues to increase for a closed low, that will slow as it moves south down the California coast, Sunday through Wednesday. This weather system is expected to dump several feet of snow in the Sierra, mainly Sunday through Monday.  In that the storm currently favors the southern portion of the Northern Sierra, south through the northern portions of the Southern Sierra, Mammoth is likely to pick up its far share from this storm.   Amounts expected will range from 6 to 10 inches near Highway 203 /395 to as much as 3 feet over the crest of Mammoth Mt. The Town of Mammoth looks to receive between a foot to 18 inches by Tuesday night, with most of it falling Sunday evening through Monday Noon.  WSW begins Sunday at 11:00AM through 11:00AM Monday.

There is still a question on how fast the system kicks through Southern Ca and if it will move East or South East through that area.  The GFS has eastern slopes up-slope developing by Tuesday afternoon while the Euro develops it Wednesday…So over all, The Euro is slower….


Dr Howard and the Dweebs…………………….:-)





A northwest Jet over Northern CA brought gusty winds and cooler temperatures today. Winds will be a lot lighter Thursday and Friday before a weak weather system brings the chance of light snow Saturday. This is a small system and I am not expecting more than an inch or two from it.  The following system is a different story. The only concern I have is that the European model slows it down and almost stalls it along the Central CA coast next week,  so that it does not come through until Wednesday night. The GFS is much more progressive and gets it out of here Tuesday.   I remember back in March, another system that got hung up off the Northern CA coast, really dumped over the northern sierra, but not much for Mammoth. All the models seem pretty progressive through Monday. This would give Mammoth Mt a good Dump Sunday and Monday, with a foot or two over the Mountain and somewhere between 6 and 10 inches in town by Tuesday AM  However, it does bother me that the EURO sort of stalls it Tuesday/Wednesday. What if it stalls off the Northern CA coast again and dumps another 5 feet over the northern sierra?  That would really be like salt on a wound this year, especially to the locals around Tahoe with the Stay and Shelter.  I will take another quick look at it Friday…

Longer Range;

The MJO is showing phase 8/1 for mid month. (Week Two) Even through it is April, you have to check the AR tools to see if there is a river (AR) headed our way. Low and behold there is one in the GFS with a closed upper high over AK.  However, before all you Weather Dweebs start salivating…..The European does not agree….   Will keep tabs and followup on this next week….


Try to stay busy doing something……

But stay healthy!!!


Dr Howard and the Dweebs………………..;-)

Last in the Series of weather system to bring light snowfall Saturday into Sunday evening……Fair to Partly cloudy next week with warmer temperatures….

It’s ironic that the best Skiing and Boarding conditions since last December have occurred this month and the Mountain is closed……No thanks to COVID 19. The parttern that dumped between 16 and 19 inches on Mammoth Mt this past week and another possibly 1 to 3 inches this weekend is winding down  A March Miracle? Certainly not the Miracle that a vaccine would deliver…


The teleconnection (-EPO) is trending positive now for the end of the month, is now expected to to become negative again in April. Some of the models show strongly negative for much of April in both ensembles of the GFS and ECMWF.   That means a lot of blocking up over Alaska is expected. That means that weather systems will tend to be more suppressed to the south over California.  This is a change to what was expected some 4 to 5 days ago.  So it may very well be that more storminess will be expected during the Month of April….


More later…


The Dweeber……………………….:-)