Mammoth Mt closes July 4th for the ski season with an amazing year!…..Although June was one of the hottest on record for the Eastern Sierra….Somewhat Cooler than normal temperatures are on the way for the rest of July…The Monsoon looks weaker than normal for July….

After a string of very warm days with temperatures some 10 to 15 degrees above normal, during the month of June, the forecast models are trending toward a much cooler month of July associated with west coast troughing in the mean. This will create a trend of breezier than normal afternoons and evenings along with high temperatures mostly in the 70s and even some 60s possible. Additionally, there will be much fewer days at and above 80 according to the guidance. This is opposed to what we had during the month of June where highs were mostly in the 80s the second half of the month.  The trough in the mean also spells the likelihood of a much weaker monsoon season which would be good from the standpoint for less lightning strikes.  Typically we get more high based thunderstorm’s here, carrying the threat for more lighting than heavy rain in July.

On the flip side, the negative here is that if this pattern actually does set up, the frequency of critical fire danger episodes would greatly increase, as short wave energy within the troughs bring a greatly enhanced zephyr, (west wind) along with strong winds for summer aloft. Furthermore, shots of very dry air from the west would likely accompany the strong gusty winds.  This is what I see based upon the current extended guidance, beginning the second half of this week. The west coast trough that is forecasted by the both GFS and ECMWF is definitely anomalous for the month of July!

Now for some encouraging news…

I have been told by one well seasoned Meteorologist from WSFO Reno that is now retired, that persistent Troughing in the Summer is linked to wetter winters here. Does this mean that the winter of 2016/2017 will be a wet one? No….it just means that from a troughy previous summer, that the incidence of wetter than normal winters are higher the following year.   However, just like the big El Nino forecast for a big winter in Southern CA last year that was a bust,  there are no guarantees.

One other item worth mentioning…  I do not know if any of you have been keeping up with solar news. The Sun has been recording several spotless days since early June.  We are rapidly headed toward another solar minimum.   There is also a link between wetter CA winters and solar minimums.


The Dweeber………………….:-)




High pressure over the far west will gradually weaken the next week…Weak upper low will destabilize the air-mass over the Central Sierra for the chance of thunderstorms this afternoon and Saturday……Shift in the upper jet further south along the west coast next Wednesday will bring an end to the stretch of 80 degree days in Mammoth and 100 degrees days in Bishop….

Saturday AM:

One small Vort center has moved on-shore near San Jose this morning,  and will approach the sierra this afternoon. Scattered thunderstorms may develop today over Western Mono County, then shift off to the east later this afternoon.  So the Town of Mammoth and June may have some rainfall today Saturday. (30%) chance.

]It will be dry Sunday through next Saturday….  Highs in Mammoth will be in the high 70s then cool to the mid to upper 70s by mid-week.  lows in the 40s  There will be a stronger Zephyr by mid-week.

The following week looks hot with the chance of the return of the summertime monsoon…



For the next few days, Mammoth will bask in low 80s but the end to our heat wave appears to be in sight now as a trough in the mean deepens over the pacific NW south to California. Breezier afternoons will develop by Tuesday or Wednesday and beyond. Highs will retreat back into the 70s with night in the 40s by Wednesday.

In the meantime, a very weak upper low will act upon strong daytime heating to initiate some thunderstorms today and Saturday.  This is not the Monsoon, rather some weak forcing from the west.

The Dweebs could not see any upper divergence in the 250mb progs this morning.  So I am skeptical about how much storminess will actually develop. This is a pattern that the models do not handle well.

For the record….the NWS is calling for scattered Thunderstorms this afternoon…today and Saturday with the pattern becoming fair by Sunday through the Holiday.  High will be near upper 70s to low 80s cooling to the 70s by Wednesday.

Dr Howard and the Dweebs…………………………:-)



Stretch of very warm temperature’s to continue in the high country as an Continental Upper high builds over 4 corners area again….Upper high is split with weak Col over Central CA….Widely scattered thunderstorms possible mid week….

Wednesday Am Update:

Very heavy rains fell in Mammoth during the mid afternoon hours Tuesday. An estimated .5 to an inch fell in town, most of which occurred within 1/2 hours.  Todays atmosphere is certainly more moist as compared to yesterday morning, however, we do not have the upper dynamics or focusing mechanism like yesterday.

So there is a chance of showers today and or thunderstorm,  However,  I do not expect a rain event like yesterday in Mammoth.

There is better focusing over the Owens Valley today and so there is a better chance of areas heavy rain within the shafts directly below any thunderstorms.  Tomorrow will begin a drying process as weak troughing sets up over the pacific NW. It will be dry over the Owens Valley Thursday.


Your Fourth of July Weekend outlook including July Fourth Monday is for slightly cooler temperature’s and drier conditions with the usual afternoon and early evening Zephyr winds 15 to 25 MPH.  Highs in Mammoth will be in the low 80 with nighttime lows in the upper 40s and 50s.


Monday Night Update:

The Dweebs can not remember a late Spring and Summer that has been so warm here in the Greater Eastern California area.  It is been 9 days straight that the high temperature has hit at least 100 at the Bishop AP. Today’s high was 106 tying the record set in 2015. Tuesday’s record is 107 should Bishop tie it. The outlook increases the chance of some thunderstorms especially Wednesday, as an easterly wave moves out of AZ. Renewed weak troughing off the coast of the Pacific NW will flush moisture eastward again. The stretch of 100+ temperatures is expected to continue with little relief in sight for the Owens Valley.


A weak *Col will help to channel some high and mid level moisture into the Central Sierra Tuesday and Wednesday for a chance of thunderstorms over Mono County.  There appears to be a weak disturbance coming out of AZ, helping to add instability to the mix. Best guess is that the Mono County convergence zone will set up where the Zephyr meets the southerly flow coming up the Owens Valley as well.  Any rainfall accumulation will be light.

Toms Place and Sunny Slopes is best spot for Mono County Convergence Zone as well as the Glass Mts…Clouds will build over the Sierra then tend to shift east a bit as the Zephyr kicks in..

The area at the top of the grade is a naturel for Summertime Convergence thunderstorm’s.

Going into the weekend, we will probably get some cooling as a weak Trof moves into the Pacific Northwest. SW flow should flush any remaining moisture out of Mono County so the weekend will be dry.  High temps the next few day will be in the Mid 80s then cool to the upper 70s by Saturday.  Lows in the 40s and 50s.


One concern worth mentioning…. The lower levels are very dry and so any thunderstorms that do develop are likely to be high based with Strong Gusty out flow winds and some lighting……Not a good set up but one we would expect here in the high county in the Summer.

Lets hope the forest dodges a bullet from any lightning related to fires, from the short period of thunderstorm’s expected mid-week

* A Col is the point of relatively lowest pressure between two upper highs….. 

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