Archive for May, 2014

Cooler Breezy Weekend to be followed by Clouds….Showers and Possible Thunderstorms Tuesday and Wednesday, with some Upper Elevation Light to Possibly Moderate Snow as well……The Memorial Day Holiday Weekend Looks Fair and Warmer with highs well into the 60s……

Tuesday AM:

No Real Changes from yesterdays discussion except to tweak the QPF and snow levels and raise temperatures over the Holiday Weekend.

This AM’s Snow level is verifying a bit lower at 6500ft. The freezing level was 7500 at 5:00AM.  The SL will rise a bit this afternoon but remain as low as 7000-7500.        Tonight, the snow level rises to 8000 and by Wednesday PM 9000 FT.

Amounts still look possible in the 6 to 8 inches range over-all over the next 3 days, depending on where exactly the upper low sets up over the Great Basin Wednesday.

The Dweebs do not expect any issues with local roads from this weather system…   With that said…..Tioga and Sonora passes may close for a day or two.  However, with as warm as it is going to get….. I would Imagine that they will be open for the Holiday weekend.

 

See the following link for up to date Tioga Road info:  http://www.dot.ca.gov/hq/roadinfo/sr120

See the following link for Sonora Road info: http://www.dot.ca.gov/hq/roadinfo/display.php?page=sr108

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Monday AM Update:

Everything looks good for a late spring storm that will bring snowfall amounts of about 6 to 7 inches at the 9000 foot level and possibly as much as 7 to 9 inches over the Mammoth Crest between Tuesday AM and Wednesday night.  The storms total QPF according to the new 12z GFS is about an inch over Extreme Southern Mono County. This is associated with the track of the upper low and its deformation axis, as it swings southeast Tuesday and then lifts NE toward NE Nevada early Wednesday morning.

According to the new 12Z GFS, the upper low comes inland over the Bay Area about midnight tonight and shifts SE to about Death Valley by 5:00pm Tuesday. It then lifts North East into Nevada Tuesday night into Wednesday morning. The Cold Pool Follows the track of the upper low to the south of it through Wednesday night. It then appears that the cold pool will sheer south Thursday as the upper low redevelops and becomes cut off over Southern CA.

According to the new 12Z Monday GFS, the snow level will be the lowest at 12Z Tuesday with its freezing level at 7700 feet at 5:00AM.  So the Town of Mammoth will have its best chances of accumulating snow of some 2 to 4 inches at 8000ft Tuesday morning. Even though there will be light accumulating snow Tuesday AM, the local roads are pretty warm and so there may not be much effect on travel locally, except over the highest elevations of town. With that said, the high elevation passes like Tioga may close for a few days but I would imagine reopen by Thursday or Friday at the latest.  The storm will be out of the high country by Thursday at the latest…… It will be a warm weekend with highs in the mid to upper 60s, both Saturday and Sunday.

QPF:

This mornings Monday 12z GFS has about an inch total of liquid EQ for Mammoth. With the snow level rising during part of the storm, the Snow to Water ratio will be less than it could be. Its Bulls-Eye is between Bishop and Big pine and paints about 1.3 inches.
Based upon the 12z GFS, 6 inches plus is reasonable at the main lodge with a bit more over the crest.  Last nights GEM (Canadian) had the Bulls-eye in the same place as this AM’s GFS with similar amounts of QPF….. however a bit more snowfall was indicated.

However, last nights 00z Monday ECMWF had the Bulls-Eye more over Central Mono County further to the north. It also suggested that there could be up to 9 or 10 inches within that Bull’s-eye.  I’ll take another look at the ECMWF’s QPF as soon as the new 12z run is finished running later this morning. Sometimes a compromise is in order…..

New ECMWF is in, with up to .9 over the crest. However it gives only light amounts Tuesday.  Most of the amounts are evidently associated with heavy convective snow showers.

HPC gives the crest about 3/4 of an inch of precip. So best guess is 6 to 8 inches over the upper elevations…. 9K to 11K

 

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Don’t forget to look toward the North Star late Friday night into early Saturday AM for a chance of viewing a new meteor shower. Earth will pass through a stream of debris from Comet 209P/LINEAR. The encounter could spark a new meteor shower. Forecasters aren’t sure how many meteors will appear; anything is possible from a complete dud to a magnificent meteor storm. Best estimates fall between 30 and 200 meteors per hour between 11:00PM May 23rd and 2:00AM, May 24th local time. Skies will be moonless after 8:15PM

 

Sunday AM Update:

All of last night model runs have the track of the upper low about the same as the Canadian GEM had earlier in the week. Its been great to see the Canadian model do so well. I would imagine that the Canadian Gov. has been spending more $$ in their computer programing and so meteorologists may have a better tool to use next winter out over the west.  At least from my perspective, I will follow the Canadian Model (GEM) more closely in the future, to see how its verification does over all.

The storm is a very significant one from a precipitation perspective, for so late in the season. Although I want to see some more model runs today and tonight, the thinking with most models is that there up to a good solid inch of QPF in it over a 48 hours period for the South Central Sierra. .  The storm will become very convective and so there will be some areas over the sierra, between Mammoth and Mt Whitney that may get up to a foot of snow, over the ridges.   Once again this will depend upon the exact track and how it swings inland across Central and South Central CA.

HPC 5 day QPF puts the Bull’s-eye of 1.2 inches, “storm total” by mid-week…Very Close to Mammoth Mt.   That’s up to a foot of snow at 10:1. Does this mean that Mammoth Mt will get a foot?  It is possible…..but my take is that as of this AM, the Bulls-Eye is a little south of our area from this mornings guidance. The Exact track of the small upper level feature will be the directive.

Here is a transcript from HPC as it pertains to the dynamics of the system and our area:

THE HIGHEST QPF ON DAY 2 SHOULD BE ASSOCIATED WITH THE BEST LIFT AND MOISTURE OVER NORTHERN CA. MID LEVEL COOLING COULD RESULT IN SOME CONVECTIVE ELEMENTS IN THE PRECIPITATION FIELD…AND THE WESTERLY LOW LEVEL FLOW WILL AID THE UPSLOPE PROCESS. A LARGE AREA OF 0.25 TO 0.50 INCHES OF QPF WAS PLACED ACROSS SOUTHERN CENTRAL OR AND NORTHERN CA. THE SLOW MOVING MID LEVEL SYSTEM REACHES SOUTHERN NV BY THE END OF DAY 3. THERE IS SOME EVIDENCE IN THE GLOBAL MODEL SOLUTIONS (MOST PROMINENT IN THE 00Z GFS) THAT A DEFORMATION ZONE COULD FORM “NORTH OF THE MID LEVEL CENTER” OVER CENTRAL NV. THE COMBINATION OF BANDED PRECIPITATION AND UPSLOPE FLOW SHOULD RESULT IN A LARGE AREA OF 0.25 TO 0.50 INCHES OF QPF ACROSS MUCH OF WESTERN AND CENTRAL NV…”AS WELL AS THE SIERRA NEVADA RANGE IN CA“.

 

I will UPDATE again later this afternoon…..

 

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

 

Saturday mornings weather was mostly clear with calm winds. High temperatures will be about the same as yesterday with highs in the upper 60s. Todays big change will be a moderate zephyr (west wind) that will develop mostly due to the upper ridge collapsing and its axis shifting eastward. Some gradient is indicated later today but the winds will be mostly Zephyr related. Today Saturday’s breezes will be in the 15 to 25 MPH range by afternoon but will mostly diminish over night then pick up again Sunday.

A 1000-500MB thickness guidance shows Surface Gradient’s with 4 bars between SFO and the Owens Valley at 00z Monday (5:00pm Sunday). So winds with Gusts of 40MPH in Mammoth is possible by late afternoon Sunday. It will be windier over the crest as well. Sundays afternoons winds are likely to continue well into the night…then diminish somewhat after midnight toward Sunrise.

A 1000-500mb thickness pool of 546DM is located just NW of the Bay area at 5:00PM Monday. A small jet let of 90knotts is onshore over Monterey Bay at this same time. Moderate divergence aloft is over the Northern Sierra Monday evening while Convergence Aloft is located NW of the Owens Valley. This cold pool and upper divergence will move inland SE over the Bay Area Monday night. Finally reaching the Mammoth area by midnight at the latest. The tighter isobars are over the Owens Valley by that afternoon and into that evening, So Wind Advisories are possible for the Bishop area Monday PM.

This thickness pool over Central CA will provide a lot of the instability for showers and thunderstorms over the Central Sierra and the Eastern Sierra Tuesday through Wednesday. Most of the precip in the Sierra is expected Tuesday and Tuesday evening. Again as mentioned earlier, the exact track of this feature is critical to where the most precip will fall. At the moment, the models are the most bullish over Central NV. This includes the GEM. However, with the high elevated heat source of the sierra, there will likely be quite a bit of convective enhanced precip going on Tuesday PM associated with the cold pool.

Latest Model guidance from last nights 00z Runs were not as bullish on moderate amounts of snowfall Tuesday and Wednesday. With between .25 and .75. So we are back with between 3 and 6 inches of Snow over the crest by Thursday PM, instead of late yesterdays 6 to 9 inches. Will update Sunday AM for snowfall totals Tuesday into Wednesday over the upper elevations based upon on tonight’s guidance …. Dr Howard and the Dweebs……………………….:-)

 

 

More Warming then Cooling Periods Ahead as we head into the Warmer Half of the Year…..Warming Trend Now in Play then Cooler over the weekend…..one last snowfall possible before mid June……

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 Weather.com

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.

 

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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….

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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!

 

Outlook:

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…………………………..:-)

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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…………………………………….:-)

 

Warming Trend peaked Thursday with little change in Temps expected for the High Country Friday…..Overall the next few weeks will be highlighted by both warming and cooling periods….Although Low temps will return to freezing by mid week….Only snow showers are expected late Monday night and Tuesday…..Another warm-up is expected into that following weekend…..A “New” Kelvin Wave is Moving into the Indian Ocean…..

PDATE VIA WEATHER LETTER MONDAY AM

http://data.mammothweather.com/landing/

 

 

Monday AM:

Nice break in the weather for the first 2 days of the week. Time to create snow storage for the next storm cycle that will begin this Wednesday. The next series of storms will be much colder and should for the most part be all snow for the Town of Mammoth except for the very beginning Wednesday afternoon.

The freezing level drops quickly late in the day Wednesday. Best estimate for snowfall for the Town of Mammoth will be 3 to 6 inches by Thursday morning; so this will be a smaller system snowfall wise, with up to a foot on Mammoth Mt.

The following storm will be colder and could bring 5 to 10 inches in town by between Friday AM into Saturday AM with up to 18 inches on Mammoth Mt. by Saturday AM. Saturday looks showery in the morning with improving weather in the afternoon into Saturday night.

The last in the series of storms will move in Sunday afternoon. The Sunday thru early Tuesday AM storm is a bigger storm that will be slower in moving. However, its main thrust “might be Southern CA “where some 4 inch amounts of rain may fall in their local foothills. This is expected to be between Sunday PM and Tuesday. For Mammoth, I expect a foot or two in town and possibly as much as 3+ feet on Mammoth Mt. So totals from the next storm cycle looks to be between 3 and 6 feet on Mammoth Mt between this Wednesday and the following Tuesday. Thereafter, I expect a long break….possibly until the next storm cycle begins sometime during the 1st week of February…I will update snowfall amounts (QPF) later this week.

 

The Dweeber………………………..:-)

 

 

 

 

Friday Evening:

Forecast on track for another hot dry first half of next week under the influence of strong High Pressure Aloft. …..Please be very careful when camping and with fire….Check with Forest Service in regards to campfires.  “Our Forests are Tinder Dry”….

Heat will peak tomorrow Saturday with highs in the mid 80s in Mammoth; then expect about 5 degrees of cooling early next week as the upper high shifts east and the upper flow back to the southwest. That is still a dry pattern. Temperature’s will begin to warm up again next Wednesday into that following weekend with a little different pattern.  A strong subtropical continental upper high develops next weekend over the deserts and there is the possibly that the upper flow will become southerly as early Thursday of Friday. The odds then will increase for thunderstorms next weekend.  Thunderstorms may begin toward next weekend or over the weekend. It looks like the upper flow becomes channeled out of the SSE as well.  According the ECMWF, there is also an easterly wave moving across Northern Mexico Thursday and so that will add to the import of moisture late next week.  Will update this coming week as the models will have a better handle on all this by Wednesday.

As per the discussion below, the suppressed state of the MJO is still over the tropical eastern pacific and will shift east and weaken into the Western Caribbean by the end of the month.  In its wake the next active convective state of MJO now over the western pacific will shift east into the Eastern Tropical Pacific increasing a large area of divergence about the end of the month. Anything from MCC’s to tropical storms may form; Details forthcoming later next week.   As the current upper high settles in over the four corners states, southerly or south easterly flow will develop by the end of next week and into the following week. So an increasing chance of thunderstorms will result into the first week of July as well. Strong tropical eastern pacific upper divergence will add to the potential for rainfall here in the Eastern Sierra the first week of July…..Stay tuned….

 

ENSO: 

We are now passed the Spring Barrier for predictability for El Nino:

Compare the #1 forecast for the NINO 3.4 region from May,  to #2 the latest June forecast.  PS, this is not the official forecast but the trend is significant!

 

Time for Angeleno’s to start building an Ark?  This is beginning to look scary…..

 

1. The Forecast May 20th through the 29th for The Nino 3.4 Region      http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd1/nino34Mon.gif

2. The Forecast June 9th through the 18th for the Nino 3.4 Region.       http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd3/nino34Mon.gif

 

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Brief Update:

There appears to be quite the warm spell in our future about mid month.  There also appears to be quite the cool spell during the last week of the month. With the cool spell, will there be much snow fall to deal with….Possibly.    Remember…the last frost with climo-support is the 21st day of June.

 

More on that early next week………

The Dweeber………:-)

 

You can see it in the upper jet when you look at the guidance. The upper jet continues to weaken and the belt of westerly’s are shrinking up. As we get further into the month of May, there is less energy in the westerly’s to push into the west coast.  Cut off lows are much more common with the chilly periods,  and such periods are shorter in duration.  Both ECMWF and the GFS Ensembles show two periods of unsettled weather. Next Tuesday into Wednesday and another about the middle of the month of May.

The current pattern is highlighted by a blocking upper high over Alaska while directly to the south, a chilly upper low of 538DM at 500MB. This low pressure system is suppressed south of the block with its upper jet pushing into the pacific North West Saturday and into Sunday.

Our warm upper ridge breaks down Friday with heights crashing over California Saturday into Sunday.  Both Saturday and Sunday look very breezy to windy over the crest as strong zephyr like winds develop Saturday and continue into Sunday.  500-1000mb thickness falls of 250 DM is expected between Friday PM and Tuesday. So about 25 degrees of cooling is expected through that period.  It is interesting to note that as the upper trof passes to the south of the Alaskan upper high, the upper flow around the upper high becomes coupled with the trof. The trof then receives a good shot of energy which digs the trof down into California Tuesday. The problem with the scenario is that the main vort center, comes through very early in the morning as well as is being over land. (Dry)  The FROPA will be Monday night.  The best chance of some showers will be Monday night through Tuesday night. In that the system is moisture starved, CRFC only gives our area a few hundreds. I guess we could get a dusting or ???  Latest QPF shows an increase to .40 over the crest so a few inches is now possible over the upper elevations. The upper trof shifts east Wednesday. Although a warm up develops Thursday into Friday, the latest guidance provides more uncertainty now on the strength of the warm-up as the EC has the upper block retrograding from AK westward and its ridge scenario is certainly weaker as compared to the GFS strong solution.

Of note, the new 12Z Friday GFS actually has what appears to be the 1st eastern pacific tropical storm of the season forming in the newly warmed equatorial waters from the latest Kelvin Wave. If she forms as progged, her name will be “Amanda” and she may affect the Southern tip of Baja or Sea of Cortez about mid month or shortly after….  May 15th is the beginning of the northeastern pacific hurricane season.

Climate:

The Dweebs are excited to note this morning that a new and may I add “Robust” Kelvin Wave has just moved into the Indian Ocean. This is the 2nd Kelvin Wave this year that will be moving east along and North of the Equator toward the western pacific and eventually east to the coasts of South America. It is thought that Kelvin Waves, which is an Air/Sea coupled wave, can jack-start El Nino by the process of upwelling then down welling very warm SSTs from the western pacific to depths approaching 300 meters. The wave travels east, then I believe surfaces toward the eastern pacific. This adds anomalous warmth to the SST’s from the central pacific to the eastern pacific which in turn increases anomalous convection over the Nino Basin.  This new Kelvin Wave is number 2 of probably 3 that will further increase SSTA’s throughout the Nino Basin this year.

This is a very significant event! 

More later on the progress of this Kelvin Wave this Spring and into the Summer……

This will be my last post until the 12th……..Adios!!!

 

Dr Howard and the Dweebs…………………….:-)