Warming Trend to Begin Thursday…..Instability aloft will bring the Slight Chance of TSRWs Thursday & Friday PM….Then a Fair Very Warm Weekend Ahead………Cooler….Windy Weather to arrive by Middle of Next Week…..

Friday AM Update:

Looks like Mammoth is ready for a couple of 80 degrees days both Sunday and Monday. However the cool down advertised is being pushed back a few days to the latter part of the week.

Here is your high temperature forecast for Mammoth the next several days.

Friday   Sat     Sun   Mon    Tue    Wed    Thurs    (Friday  through Sunday)

76          78      80     80        75       75        72                 60s

It will be Quite Breezy beginning Wednesday afternoon


Thursday AM Update:

It appears that certain locations in elevation for Eastern CA will be pushing near record high’s by Sunday, and especially Inyo County into Monday as well before the aforementioned cool down begins next week….  It would not surprise the Dweebs if we hit 80F on Sunday…..


Wednesday AM Update:

RE: Longer Range Outlooks

In yesterdays discussion…the Dweebs indicated that it was fairly certain that  the MJO was headed to Phase 4. (Maritime Continent). That was recently corroborated by the CPC in their latest discussion.

From the CPC:

“Dynamical model MJO forecasts differ on the forecast of the MJO in WH-RMM phase space, although agreement has increased slightly during the past 48 hours. The GFS ensemble depicts a weak signal over the Indian Ocean with a stronger signal emerging in Phase 3 during Week-2. The ECMWF and UKMET models indicate an emergence in Phase 4 with propagation toward Phase 5. The latter solutions are favored as much of the signal is likely related to faster moving Kelvin Waves.

Sensibly, the point here is most related to what temperatures will do in the Sierra high country over the next few weeks. The location of the tropical convection will most likely shift to the Maritime Continent (phase 4) later next week and then shift over the western pacific (Phase 5)  where the high frequency base state of the Kelvin wave moves the convection to phase 5…..weakening, possibly over phase space 6.  Beyond the next 5 days of anomalous warm weather, W/ Highs in the mid to upper 70s in Mammoth)…..The eastward Shift of convection increases the amplitude of the westerlies and allows a series of colder short waves into the pacific northwest then great basin, during the latter part of week 2 and possibly into week 3. The main effect to Mammoth Lakes will be on our temperatures and winds here in Mammoth.  It looks to be quite breezy, then cooler during the 2nd half of next week….and possibly into the following week as well;  based upon the MJO temperature and 500hpa composites.  Our normal highs are in the upper 60s now for Mammoth Lakes.

We will be in the mid 70s the next 5 days. I expect cooling well down into the 60s prior to the end of next week and, “a possibly freeze” at some point before fathers day.

This outlook is based upon the MJO temperature Composite’s for June over California, The chilly Trof over the northern great basin showed by the ECMWF is easily correlated for week 2.

The CPC does indicate that the MJO or in this case,  tropical convection more associated with the high frequency Kelvin Wave will play the part of normal to cooler than normal temperatures for weeks 2 and possibly 3.


Dr Howard and the Dweebs………………


Tuesday AM UPDATE:

Just a note to mention that if you missed it yesterday…Mammoth had a brief shower in the Mid-Afternoon. The interesting part about it was that during the shower, the clouds were gone. Obviously they had been blown ENE before the rain hit the ground. The weak upper jet that enhanced instability yesterday is not present today. However it will be back Thursday with even warmer temps. This sets up a better chance of some showers or thunderstorms for the high country Thursday PM as the air mass will be more unstable because of the warmer surface.  All in all, it is not going to be a big deal. The most sensible part of the pattern the rest of this week is that is it going to warm up over the next few days leading to a spectacular warm weekend (75F Saturday and Sunday). Highs in Bishop may hit 100 by Sunday.

Outlook:  Here comes the fun part. I love when there is a connection between the MJO and the weather over the Sierra.  Actually, it will be a synoptic scale change to cooler weather over the far west. There will be wind, clouds and the potential for Freezing temps in Mammoth during the 2nd half of next week.

What happening?   The convective phase of the MJO is forecasted to move into the Maritime Continent:     SEE: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_full.gif   (Yes I am buying the ECMWF MJO chart because the GFS has the Trof in the guidance as well, but not in the MJO chart)

The Odds of at least normal to below normal temperatures are pretty good!  See:  http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/Composites/Temperature/MJO-T-composites0.shtml

The 15 Day guidance has a pretty good Trof (Not Surprisingly) digging in over the far west after the middle of next week.  This is especially evident in the ECMWF week 2 model.





Dry Weekend on Tap…Breezy in the PM with some afternoon clouds……Expect afternoon Cu build-ups next week with a few high based thunderstorms possible, Mainly East of Highway 395….


Sunday PM Update: The dominate upper feature over the far west is a strong and persistent upper subtropical high pressure system that is over NW Mexico that will shift west a bit over Central Baja next week.  It will provide for above normal temperatures well into the new week. To the north, the westerlies have their own agenda governed by where the long wave upper ridging is upstream. In the meantime, a weak Trof off shore will allow a continuation of surface pressures to be higher from west to east and so the Mono Zephyr will range from light to moderate at times. The pattern is dry as a bone with little chance of any rain as the Dweebs see it. Although several small Vort maxes traverse the sierra, the afternoon zephyr will likely keep the Mono Convergence zone well to the east of Mammoth, more over the Whites where south winds blow up the Owens Valley and clash with the west afternoon wind.  So expect periods of build ups here and there will little rain if at all. Longer Range:  The climatology usually has the last Frost around Mammoth, Fathers day. Of course that date is not set in stone. However, I would expect one more meaningful long wave trof off shore with wind, cooling and even a chance of a few showers.  This year, Father’s Day is early occurring on the 15th. The last frost is usually the 21st; so between the father’s day weekend and the following weekend, the weather may become a little unsettled.  just a heads up that another cool down with winds will most likely occur before Summer sets in for good.  Looking at the EC Ensembles, the ECMWF really is not all that aggressive with that idea at all. However, the GFS between the 15th and the end of Spring try’s to bring in a cool Great Basin upper low.  So we all have some time to watch it. What ever it is, it’s not going to be a big deal.  The time frame begins about the 11th, through the 22nd. ————————————————————————————————————————————————————————————————————————————————————-


Weak low pressure trofing in the mid levels and aloft will continue to bring occasional high clouds along with light to moderate breezes the next 5 day.  Temperatures will continue in the upper 60s during the afternoon with night-time lows in the 30s. An increase to the low 70s is likely by Sunday or Monday. The overall pattern shows by the Dweebs favorite models for the next week,  looks to consist of an upper level trof axis along the west coast,  with several vort centers that will migrate through the state of CA. One will come though Monday and another about Wednesday.  Moisture is very limited and so the type of thunderstorms that may occur would be high based and diurnal.  This will bring some threat of lighting fires to the Southern Sierra next week along with gusty winds Longer Range: Per week 2 and 3- CFS About the 3rd week of June… 1. A stronger low pressure trof may bring some light precipitation to the sierra. (Gusty Winds…Cooler temps then TSRWs possible during 3rd week) 2. With Monsoon season about 6 weeks away, some of the global models already showing the Sierra Madres of Old Mexico waking up by Mid June and a draw up of moisture into New Mexico by 3rd-4th week of June.

The Week Ahead Looks Dry, Cooler and Breezy with a Slight Chance of Thunderstorms by Weeks End….High Temps to cool to near Normal late this Week…..

Tuesday AM Update:

Looking down the road….

Here is an outlook for the next two weeks…..

The Positive height anomaly in the Gulf of AK is forecasted to very slowly retrograde westward toward 160west over the next 2 weeks. Through the process, Upper troughing seems to have found a new home and so the clash of the air-masses  between the west coast trof and the heat over the Great Basin will dominate our local weather for sometime to come.  This is a typical spring pattern of dryness and often times breezy weather for Mammoth Lakes with little hope of precipitation other then a few isolated convective thunderstorms on rare occasions. There will be Lake Wind Advisories  from time to time so if your boat fishing on area lakes, be sure to check with the latest forecast for Afternoon winds before going out each morning….The pattern appears to be supported by the MJO in Phase Space 2 for May/June. So be ready for a persistent breezy pattern that will be with us more often than not for the next week or two……….

In time….Heights will rise and temps recover back into the 70s…but not until closer to mid June.

Here is your temperature forecast for the Town of Mammoth this week……….

SUNY    SUNY    SUNY    SUNY    PC        PC         PC

Tues     Wed     Thur      Fri          Sat       Sun        Mon
/73    42/68    38/68    39/66    40/63    35/62    35/64


Next Update this Weekend……………………….


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



Our warm up peaked Sunday with a high temperatures of 75 degrees in the Town of Mammoth……Both Monday and Tuesday will be about 74. The upper ridge weakens and will eventually give way to troughing along the West Coast by mid-week. This time of the year, troughing usually brings normal to below normal temperatures….with notably breezy weather. Occasionally, an upper trof will reload with a stronger short wave that will cut off a low in the bottom of the long wave trof. Whether that happens or not it will not be until the end of this week. A cut off low if far enough south can give us a thunderstorm pattern over the sierra. So far the models keep this feature too far to the north next weekend….So only a slight chance is warranted.

In the meantime, high temps will remain in the mid 70s through Tuesday, then a slow cool down will take place through the end of the week.   High temperatures will cool nearly 15 degrees to near 60 by next Sunday.  It will be a breezy week in Mammoth. SW winds will blow most afternoons with stronger breezes that will blow through the night and stronger winds yet on Wednesday approaching 40 to 45 MPH in town and gusts to 65 over the crest.  This is all part of a pattern that is being influenced by the developing El Nino that will keep our weather quite breezy at times going into the Summer.


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