Blocking Pattern to continues through Mid Week then weakens a bit toward next weekend…..However, East Asian Jet Stream remains retracted from the west coast……

The weather sensibly over the next 3 to 4 days remains virtually unchanged. Thereafter, expect a gradual cool down beginning Wednesday through the following Friday with considerable high clouds over head and WSW breezes. This change comes about as the current portion for the large scale pattern affecting California weakens enough, allowing short wave action from the west to either come through California greatly dampened, or stalling out off shore. The main point of the pattern change is not really a change. Rather, it is one of de-amplification, that allows over running of our west coast ridge. This will result in an increase of high clouds, cooler temperatures and a slight chance of showers later next week. I do not expect much in the way of anything significant from precipitation. The pattern over all looks drier than normal for the next two weeks at least….

Curiosities worth thinking about…..

  1. The warm water pool that was near the west coast in September has redeveloped some 1500 miles further WNW at 150W. It is in a position, should an upper height anomaly favor its location, set up a long wave trof with axis over the far west…. Not Bad..
  2. Some Models show a strong, highly amplified MJO the next few weeks.  However, this time, there appears to be little affect on the mid latitude circulation. The GFS week 2 progs show cool short wave energy approaching the west coast with slight chance of light precipitation, while the ECMWF dives the MJO toward the circle of death near the Rimm Phase 8/1 in its climate models and the outlook remains dry. The ECMWF is an air/sea coupled model. I believe that It is better than the GFS with the MJO at distance. As long as the MJO is not propagating strongly in the key phases in the ECMWF, I am not going to be a believer in buying into an extended EAJ at any time now in the near or distant future.  One thing that is becoming more apparent for this Fall/Winter. It may be quite the humbling winter for forecasters, when the storms finally start rolling toward the west coast with some storms making it and others forecasted to make, do not. So…Some will split when they are not supposed to.
  3. CPC is telling us in their discussion that the +(IOD) will create La Nina like conditions at times with a retracted EAJ. (East Asian Jet Stream)   So has indicated in my earlier discussion, the pattern will likely go from a total blocking pattern to one of west coast split flows, later in this season. The Warm Pool in its current location suggests the possibility of some very cold western Arctic outbreaks in December as well.  Should the EAJ get modulated somehow from the tropics to the west coast, were off to the races.  However, at this time, I do not see any horses…..
  4. I will have an update later Tuesday or early Wednesday after the updated CPC discussion.

The Dweeber……..




Stable weather with above normal temperatures to continue this week as Large Scale Omega Block in the mean persists…….Expect the current Ridge Trough pattern to weaken a bit about mid month with some unsettled weather possible….


No changes in the short or medium range


Some changes are showing up in the GFS this morning around the 15th to the 21st. The GFS tries to bring in some short wave energy to the west coast. The Dweebs have indicated for sometime that the pattern would de-amplify around then,  simply because the Hudson Bay Low Kicks out, creating an excessive wavelength. As result, some short wave energy will reach the west coast. However, simply put, that does not mean we will get a good storm. It means that well get some clouds, possibly some breezes and some cooling, possibly some showers. The ECMWF as well as most other models do not bring any significant short wave energy into our area at that time…..


European Long Range:


Much More Optimistic..

It says that although the month of November will be drier than normal, The tempo really picks up during the 2nd week of December, so that the Christmas Holidays look very good with abundant snowfall before hand.


The Dweeber…….:-)




The western hemispheric Omega Block is well establishes now and is likely to continue for some time. And although it will begin to weaken toward mid month, allowing some storm energy to reach the west coast. As indicted in past discussions, the EAJ is retracted and in this case, may be being forced by the +IOD in the Indian Ocean.  In that the QBO is in its positive phase with a deep, for this time of the year, Hudson Bay Low. That is helping to anchor the Omega Block pattern over the far west..

The +(IOD) has created a low frequency tropical state in which anomalous tropical convection is displaced both further west, south of the Arabian Sea and at times further east of the western pacific. This is having an affect on the EAJ I believe.

The next expectation, is that the current cycle of the Hudson Bay Low will come to an end, as it  “kicks out east” toward mid month. This allows the wavelength of the westerlies to deamplify.  Initially, this should allow some shortwave energy to reassert itself through the mean ridge position long the west coast. That would bring showers and colder weather. It is way too soon to know if this will be an inside or coastal slider. Better Visibility later this week….Stay Tuned.

Will the Hudson Bay Low redevelop for another long term cycle? Only time will tell…..


The MJO…

Although the MJO shows strongly through Phase 8 in the GFS next week, I think that is bogus as the *ECMWF is not in agreement.

*Remember, the European model has more computing power than the GFS model. It uses data continuously to make a forecast, rather than just four times per day. Statistically, it has been more accurate than the GFS. Additionally, ensembles are used to test different variables in forecasting equations.

Sensible Weather… For Mammoth LAKES

Dry this week.   Light winds..

Highs in the low to mid 60s. Lows in the upper 20s and low 30s.


The Dweeber………

Near Record Cold Over the Weekend supplying wind energy for the Southland today……Next shot of Great Basin energy on the way……

November 1st;

The weather pattern continues dry for the eastern sierra.  Stronger inversions are developing now and so temperatures aloft are not as cold. There are two global models that I usually compare most of the time. The ECMWF (euro)  The GFS (american)  On occasion, the JMAN Japanese (ensemble) and Canadian. (GEM)

All are dryer than normal for November,  The November outlook is arriving soon.   The big issue here I think is the ongoing strong IOD Indian Ocean Dipole in its positive phase. It is responsible for below normal convection over the Maritime Continent to the Western Pacific. This often times will shift the tropical convection over the Western Hemi further east and as a result, teleconnection often favor a Trof in the east and ridge in the west. Not all the time, but often enough to make a difference in normal amounts of precipitation over CA. The +IOD will most likely weaken toward the end of the Winter.  The European model is an air-sea coupled model and may have a better handle on the longer range this winter as compared to the GFS.  We’ll see…. At the moment, the GFS has the MJO into phase 8-1 around mid month. That would be positive for a storm or two for Mammoth. Those MJO Phases often pulls the upper, Eastern Pacific high far enough north to allow some undercutting of the westerlies to the west coast. However, the ECMWF does not get it there….Thus it continues to be drier than normal through mid month. The climate model portion of the ECMWF shows a few feet of snow for Mammoth as we go from Mid Month to the end of the month.  The Dweebs will keep you all in the loop on this.


Dr Howard and the Dweebs…………………..:-)


Mammoth Residents had a rude awaiting Sunday morning as the low temperatures of the early morning did not change all that much during the afternoon. Mammoth even experienced some light snow flurry action for a time. Mammoth’s high temperature was confined to the mid 20’s on Sunday while in Bishop Ca, the high temperature nearly broke a record high-low of 49. This was a degree above the all time record High -Low set back in 1991 for the date.  In Mammoth Lakes, the high was 26 degrees, possibly a record, High-Low?

The wave that pulled through Sunday morning pulled Northern Rockies cold air into our area. In back of the upper Trof and surface front, high pressure at the surface built in, and was accompanied by strong subsidence aloft. Then forced down sloping winds to the west of the Sierra and south to the mountains, east of LA created fire storm conditions to those regions.

Gradients will begin to relax today and into tonight for the high country. However, another dry cold dynamic system will push into the Sierra Tuesday, and build pressures at the surface Tuesday night into Wednesday for another Offshore Wind event, and this time, possibly on steroids for the south.  The upper jet appears to be stronger with this system for Tuesday with stronger convergence aloft in the Right Front Quad of the upper jet.   Once again, this is a dry system.


This looks to be the last of the Santana wind events for a while. Hopefully the last, even if that’s wishful thinking….


As far as a real snow storm for Mammoth?…..We’ll have to see what mother nature deals out for us for the middle of November…..


Dr Howard and the Dweebs…………………..:-)



Looking at the GFS Ensemble for the MJO,  there is an interesting curiosity developing in the MJO RIM with 1.5 Sigma in phases 1/8.

This is the time frame during the 2nd week of November. The MJO Lagg composites suggest at least weak west coast troughing during this period in November.

This is just something to watch…….