Friday PM Update:

Latest Guidance today from the GFS and ECM gives Mammoth Mt 6 to 9 inches of Snow Middle of next week…..Now that’s Significant!!

Better wax-up up if you’re coming for the Holiday!


Prepare for an upcoming Meteor Shower over the Memorial Day Holiday Weekend….If you coming to Mammoth for the Holiday, you could not have chosen a better place for viewing….so save the Date….

From Space

GET READY FOR A NEW METEOR SHOWER: May 24th could be a big day for meteor astronomy. That’s when Earth is expected to pass through a cloud of debris from comet 209P/LINEAR, producing a never-before-seen meteor shower. Meteor rates could exceed 200 per hour, and some forecasters have even mentioned the possibility of a meteor storm. Get the full story from Science@NASA.


Friday AM Update:

Well…..I got to give credit where credit is due.  That Canadian model is doing a good job for the west coast by picking up on a secondary impulse, developing it into a closed low and keeping it just off the west coast as it heads south to the Bay Area By Tuesday AM. It has been more consistent in the number of ensembles members, than both the GFS and ECMWF which now have pretty much the same game plan. This means that the odds are increasing for another good shot of snowfall for the high country anytime after midnight Monday through Wednesday. Between all the models, the QPF from last nights runs varied from as little as a third of an inch for the Mammoth Crest, to as high as an inch of water EQ. This means that Mammoth could get about 4 to 5+ inches over the highest elevations by Midweek. This is significant! Especially coming before the closing of Mammoth Mountain, after the Memorial Day holiday weekend.

Will Update Again This Weekend…..

In the meantime, it will be another warm beautiful day today with highs in the low 70s. A mild Zephyr will show up this afternoon, but will subside by evening…..  Tomorrow’s Zephyr will be stronger and will continue further into the evening. Sundays southwest winds will be even stronger as winds will be gradient driven. They will likely continue through the night.  Temps will begin there cool down Saturday with further cooling is expected into Tuesday.  High temperature anomalies will range from +15f today to -10f by Tuesday. This is all great news for Southern California as the Dweebs know how hot it has been lately. Here is something else to consider. The Pacific Decadal Oscillation has, as of March, turned strongly positive. SSTS along the west coast are really warming up. I do not know if this is a short-term phenomena or that this switch will last longer term.  However, the big message here is that over the past several years, June Gloom along the coastal section of California has been much more prevalent…lasting well into the Summer. With the PDO going positive and a warm ENSO event possible this Summer, the coastal areas of the state with warmer water, (SSTS) will have a shorter June Gloom season and much better beach weather this Summer. On the negative side, a lot of folks who do not have AC, may become uncomfortable, as it will become more warm and humid as well.

Dr Howard and the Dweebs……………………..:-)


Here below from “Weatherwest” is a post worth noting….

It discusses the new Kelvin Wave that according to the CPC has reached the Maritime Continent and will be moving into the Western Pacific Shortly.

A new Kelvin Wave appears to be forming in the West Pacific in response to the strong WWBs earlier this year, which is likely to send another pulse of warm water eastward over the next 1-2 months. In the relatively short-term, numerical models suggest that a fairly strong WWB will occur this week much further east than as yet been observed during the current event.  This is potentially an important event in the evolution of El Niño, since this temporary 180-degree reversal of the winds in the Niño 3.4 region will essentially shut down whatever weak upwelling remains in the far eastern Pacific. If this event comes to pass as currently projected in the models, I’d expect rapid SST warming to continue and expand westward over the next 2 weeks. With additional major West Pacific WWBs slated for early summer, wind conditions appear to be favorable for the maintenance of the already-developing second major Kelvin wave and perhaps even the formation of a third later this summer. There is currently no evidence of a sub-surface cool pool developing in the West Pacific after the passage of the huge Kelvin wave a couple of months ago, which effectively means that there’s no obvious “kill switch” that would have the potential to shut down this developing El Niño event before it really gets going. In other words: a repeat of summer 2012–where early-season signs of a developing event ultimately collapsed, leading to failed forecasts and much consternation–appears to be very unlikely.



Late Thursday AM  (11:37)

New 12z ECMWF has closed 500MB low coming down the coast similar to last night GEM, while the new 12Z Thursday GEM is more like last nights ECMWF.   The new 12z Thursday GFS is now the outliner with its more progressive solution next week…..More fun to come!


Thursday AM:

Again…I am not a fan of the Canadian Model for the far west but it is really tracking this system west down the California coast in the extended period. (Next Week)  In fact it cuts off (Detaches)  the upper low so much from the westerlies that the upper system is left to spin over the southern part of the state through the following holiday weekend.  That if played out would keep temps a bit cooler than normal for our high country. The EC and GFS are consistently better performers for the far west. They are further east with the system and not as cut off.  So well just have to play a wait and see how this all develops the next week.

In the meantime the heat is on!   Record highs are expected today in Mammoth and near record highs for tomorrow Friday.  Today record of 70 degrees was set back in 2007. Tomorrows record if reached is 74 set back in 2006.  That is doubtful as the upper ridge will be beginning to break down and a moderate Zephyr wind is expected to develop in the afternoon.  It will be very breezy over the weekend.

As a note… we may just be beginning to get taste of what may end up as a long hot summer in California…….


The Dweeber……………………….


Wednesday AM Update:

An interesting twist to the Models the past 24 hours indicates that the upper trof will dig further west over California instead of over the Great Basin as indicated in the Tuesday Am update. As mentioned yesterday, the majority of the precip will be contained within the upper closed center itself. That now is taking a track more over the Sierra itself Monday night into Tuesday. The ECMWF shows the upper low at 500mb pretty much being cut off over Central CA Tuesday and lingering it through Thursday while the GFS is more progressive taking the center and opening it up after Tuesday which would keep some of the cool around mid-week but the chance of any significant showers would shift east more into the Rockies Wednesday.  Overall the most interesting part of this pattern as forecasted by the models is that the GEM (The Canadian), caught on to the further west track before either the EC or GFS. I usually do not pay much attention to the GEM as its performance is not as reliable over the far west CONUS as either the EC or the GFS.

As far as the QPF, the ECMWF does suggest significant precipitation with this system. In fact it paints upwards to between .5 and .7 for the sierra crest. The GFS on the other had is drier as it ejects the system out of our area sooner with only about a quarter of an inch in that model.  Remember in a storm like the one that is coming in early next week, given the highly convective potential of this system Tuesday…..Thunderstorms can produce localized heavy showers and Hail. The main area of that potential will be fine tuned next Monday AM and again Tuesday AM.


Mammoth Lakes High temps will be in the low to mid 70s through Friday, then cool to near 70 by Saturday and then 60s Sunday, with 50s Monday through Wednesday. Night time lows will be in the 30s the next few day then cool into the 20s early next week.

Afternoon breezes (zephyr) with develop Friday PM with stronger west winds developing Saturday afternoon into Sunday night ahead of the digging trof. There will likely be some light snowfall Monday night into Tuesday over the upper elevations.  Will fine tune amounts over the weekend.

Again a lot will depend upon the exact track of the upper center and of course its timing…..


Memorial Weekend Update:

The upshot here is that the American models still forecast a ridge for the upcoming holiday weekend more suggestive of highs closer to the upper 60s or even 70. while the ECMWF has more of a zonal flow with above normal heights. That suggests that temps will be cooler (low 60s) than the GFS and that it will be breezy as well. So a compromise would be a warming trend through the holiday weekend with highs climbing to the mid 60s in town for the holiday…… pretty nice here in town for the end of the ski season with spring conditions prevailing….

New CFS update this morning shows the possibility of more storminess in June….


Tuesday AM Update:

Record Heat for Mammoth Thursday with high temps in the mid 70s and for Bishop Friday with highs in the mid 90s…..Freezing level to jump to 15K Thursday night!



Both EC and GFS models are a bit more aggressive in breaking down the upper ridge now over CA this weekend.  It looks like we will have some pretty strong breezes Saturday into Sunday in the high country. It will grow cooler as well over the weekend and into next week.  Several scenarios for showers are possible. However, the latest 12Z Tuesday GFS shows a closed low at 500MB stacked above the same at 700MB to develop along the northern NV/Utah Border by Tuesday AM. At 700MB an area of 70% RH is over or near the Eastern slopes of the central sierra. The upper flow is from the NNE and so some upslope showers or even some Thunder is possible Between Monday Evening and Tuesday Evening. Best Thunder chances would be with daytime heating convectively.  Any showers or thunder Monday PM would be more associated with a Vort center near SFO Monday AM, moving over the SJV that afternoon into the evening.

Longer Range outlook (Memorial Day Weekend) ( First Look)

The Weather Pattern according to this mornings 12Z GFS Guidance suggests another significant upper ridge that builds into California Friday into Saturday from the SW with an off shore flow. The upper ridge becomes East-West orientated by Memorial Day with its axis over North Central CA. This is a toasty pattern for Southern CA and a pattern that will allow only light Zephyr breezes for Mammoth area during the Afternoon hours.  So Mammoth Visitors…be ready for a Fab Weekend weather-wise!

Expect Daytime highs 65 to 70 in Mammoth Saturday and Sunday for the Memorial Day Holiday Weekend and nighttime lows in the 30s.

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


My annual pilgrimage to the tip of Baja is now over and it is interesting to note that the waters off the coast of the tip of Baja are warmer then I can remember for so early in the year.  SSTs of near 80 degrees in May in my experience is unusual for this early in the season of Spring. No doubt a result of the growing El Nino and the results of the latest Kelvin Wave to move across the pacific.

Time to look ahead and to note that the Climate Forecast System is still out looking the possibility of one last snow producing system between the end of May and the end of the first week of June. Remember, the CFS is not the same kind of model as the GFS or even the ECMWF. Its makeup includes additional features that are more climate related. It is interesting to compare the global models and their ensembles as well as the location of the MJO and its composites for that period for support in its forecast. The MJOs composites for the month of May for phase 3, still has a slight weakness effecting the west coast or another way to view it,  is that there is no strong positive upper height anomaly either. Both global models EC and GFS control ensemble has a couple of storms worth watching. One weaker one this upcoming weekend that may produce, wind, cooling and possibly a few showers and a stronger one, about the end of the month. The stronger one may get cut off, off shore as suggested by one of the models. The CFS has the possibility of precip between the end of the month of May and the end of the 1st week of June.

As far as sensible weather…its going to get warm!  In fact high temperature records maybe in jeopardy by Friday. What does that mean for the region?…..highs in the mid 90s Thursday, Friday and Saturday for the Bishop area and Low to mid 70s in Mammoth.  There is a weather system worth noting for the end of the week that will bring, at the least, some wind, cooling and possibly some isolated convective showers by Monday.


As we wind up the end of the ski season with the Memorial Day Holiday, a look at both ensembles of the ECMWF and GFS shows no major storms for our area. Overall…temps will remain above normal….


OF NOTE;   The EC control was a bit more aggressive with last nights run showing an additional impulse coming into CA early next week so there may be a few showers a week from now next Monday or Tuesday. The GFS is pretty dry, but may flip wetter.  Beyond next Monday, the ECMWF does have a little weather that may bring some showers to the high country….overall the systems seem to be more of nuisance than anything else, however it will definitely be cooler for a few days.

Even though there will be some cooler periods….temperatures will remain above normal over all….right on through the Memorial Day Holiday….

Retrogression is forecasted by both global models the end of the month leading to the possibility of some unsettled weather for the first week of June.  This maybe what the CFS is looking at……”Winters last gasp!”


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