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AbruptSLR

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Re: 2014 El Nino?
« Reply #1300 on: July 18, 2014, 03:31:40 AM »
The attached 30-day moving average SOI issued by BoM on July 18 2014 indicates a current value of -6.9

bigB,

To be honest, this past February I knew almost nothing about the ENSO, and two years ago I new almost nothing about Antarctica, sea level rise, or climate change.  It just shows what Neven's blog and the internet can teach a guy.

Best,
ASLR
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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bigB

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Re: 2014 El Nino?
« Reply #1301 on: July 18, 2014, 04:36:07 AM »
Attached is the EMC/MMAB RTG SSTA image updated, July 17. Which shows basically the same thing posted in my previous post as well the post made by Deep Octo. This image provides a good view of the warm SSTA stretching across the Equatorial Pacific from 0-5N while cooler SSTA stretch across the Equatorial Pacific from 0-5S. Especially in the Central Equatorial Pacific/edge of the Eastern Equatorial Pacific as a weak upwelling phase pushes east. The pocket of slightly warm SSTA seen in the Western Equatorial Pacific around 170E appears to be associated with the new weak downwelling phase of our next kelvin wave.

ASLR,

Agreed, this is a great forum and one can learn a lot here, Thank you Neven for providing such a place!

bigB

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Re: 2014 El Nino?
« Reply #1302 on: July 18, 2014, 07:58:31 AM »
I just stumbled across the attached image which shows the relationship between high and low pressure and cool and warm SST regarding the SOI during La Nina(top), Neutral(center), and El Nino(bottom). As I have previously mentioned, high SLP pressure is found over cool SST while low SLP is found over warm SST. Most of us already know this though. I have attached the following link to the site where this image was obtained. The site provides information on Rossby waves, Kelvin waves, heat distribution in the Pacific, and ENSO cycles, focusing mostly on the 97-98 El Nino. Very interesting and worth checking out.

https://www.eeb.ucla.edu/test/faculty/nezlin/ElNino.htm#Section1

Neven

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Re: 2014 El Nino?
« Reply #1303 on: July 18, 2014, 10:01:03 AM »
Agreed, this is a great forum and one can learn a lot here, Thank you Neven for providing such a place!

Thanks, but it would be nothing without its commenters.  :)
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bigB

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Re: 2014 El Nino?
« Reply #1304 on: July 18, 2014, 07:51:35 PM »
Attached are the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site, updated July 18. The slow rising(becoming less negative) trend in 30 day avg SOI values continues. GFS forecast models for SLP at Darwin and Tahiti suggest this slow rising trend will continue for the next several days. Also, it appears the active phase of the MJO is weakening and may not make it to the central pacific.

AbruptSLR

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Re: 2014 El Nino?
« Reply #1305 on: July 18, 2014, 09:48:01 PM »
While the two attached MJO forecasts issued July 18 2014 both indicate that the active phase of the MJO has returned to the eastern edge of the Maritime Continent (as forecast yesterday by the ECMM but not by the GFS), the first attached image by the ECMM shows the MJO strengthening with in the Maritime Continent, while the second attached image by the GFS shows the MJO's strength dropping rapidly.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1306 on: July 19, 2014, 02:15:59 AM »
I am traveling now, and for the next two days, so I do not have time to wait for the BoM to update their 30-day moving average SOI plot, so here is their data issued July 19 2014 (Sydney Time) with a current value of -5.3:

20140618,20140717,-5.3

edit: Here is the associated plot:
« Last Edit: July 19, 2014, 07:33:30 AM by AbruptSLR »
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bigB

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Re: 2014 El Nino?
« Reply #1307 on: July 19, 2014, 03:29:31 AM »
Attached is the EMC/MMAB High Resolution RTG SSTA image updated July 18, which shows the upwelling phase creeping ever closer to the Eastern Pacific. Also, it shows that warm SSTA have built up over the last few days between the Galapagos Islands and Ecuador/Peru. Surface wind and ocean current maps(see second attachment of the real time earth maps), suggest this warm water is being held in place by weak westerly wind and equatorial currents just of shore of South America. NOAA's OSPO SSTA image is the only model updated in the last 24 hours that does not show this. However, the cool upwelling phase of the Kelvin wave cycle is pushing closer and closer towards the Americas (Ecuador/Peru to be exact). With relatively weak but cool water in place underneath whatever warm subsurface water is left from the last downwelling Kelvin wave cycle. I suspect its only a matter of time. Hopefully, what appears to be a new downwelling Kelvin wave in Western Pacific, will continue building over the next few weeks as it begins to push east. At the moment, I still believe there's a good chance for a weak-moderate El Nino this coming late Fall/early Winter. Simply because the cool water lurking beneath the Equatorial Pacific is rather weak. It would NOT take another massive Kelvin wave to warm things back up after this cool down occurs. This is actually a similar pattern to what one would expect to see if a weak-moderate El Nino were to develop. Meaning, instead of building through the whole Spring, Summer, and into the Fall like a strong El Nino typically does, a brief cool down would occur mid summer do to an upwelling kelvin wave cycle impacting the South America. While at the same time a new downwelling Kelvin wave would be building in the Western Pacific, impacting South America by early Fall and building into a weak-moderate El Nino by very late Fall and peaking by winter. 91/92, 02/03, and sort of the 09/10 are some recent good examples of this.(see third attachment). Of course we could end up with a repeat of 2012, but two busts within two years of this magnitude is very uncommon. It could happen though. Anything is possible, but I believe at worst case scenario, we get a ENSO-neutral. Anything other than La Nina, which I just don’t see happening at the moment. ASLR, Safe travels.


deep octopus

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Re: 2014 El Nino?
« Reply #1308 on: July 19, 2014, 05:42:05 AM »
1991/1992 is actually a good example of what you are describing. Looking at the weekly data, NIño 3.4 spiked to a high of 0.9 C on June 26, 1991, and again on July 31, before slipping to 0.1 C on September 11, 1991. It didn't take but a month for it to spike back to 1.1 C on October 16, 1991, and then an ultimate peak of 2.0 C on December 18, 1991. In other words... a condition for a week-long period consistent with the colloquial definition of "super" El Niño (though this was far too brief to maintain and warrant calling 1991/1992 more than a strong-moderate El Niño.) And yes, other regions (Niño 1+2, 3, and 4) all experienced a cooling during August and early September 1991, so it was a short cooling of the entire Pacific. Looking at subsurface data, it seems that there was an initial downwelling Kelvin wave that was warming the surface during July and had broad coverage over the basin, before cool water partitioned the warm water in half, thus budding "another" downwelling Kelvin wave to the west. That one gained momentum and powered through the autumn months.

http://www.cpc.ncep.noaa.gov/data/indices/wksst8110.for









Upper ocean heat, though, is no longer present today to sustain an El Niño. That accumulated heat has been lost in the westward-propagating Rossby waves or was released as latent heat during those very strong hurricanes off of Mexico. And so a new downwelling Kelvin wave incoming from the west is how this will gain any traction. I thought this event was about dead in the water (no pun intended), but there is potentially some new downwelling activity taking place as warm water pockets gather in the west below the surface. If MJO continues to hold in the Maritime Continental region, those odds stay up.

I also don't see the odds of La Niña as very good, though if we're talking merely about consequences, I don't think the drought in the southwestern US will improve without at least a moderate El Niño. Global surface temperatures will probably still punch to record highs in 2015 as long as no oceanic cooling occurs to bury heat.

bigB

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Re: 2014 El Nino?
« Reply #1309 on: July 19, 2014, 09:50:30 PM »
Deep Octo,

Thanks for posting the subsurface profile of the 91/92 El Nino. Not that im convinced we're on our way to having an El Nino, but its absolutely not at all out of the question. Not quite yet at least. I do agree, a weak El Nino or ENSO-neutral would not do much in the way of drought busting. It would provide at least something closer to what one would expect to see during a year with avg rainfall. Still, all that would do at this point is hold off the drought for a few months. Something like the 91-92 El Nino would be nice, as it helped provide some relief during the 90/91 drought(which was worse for So Cal at the time than the current 2014 drought thus far, but we're getting there). Of course the early/mid 1990's ended up being what seemed like a multi year El Nino. We actually had some of the worst flooding ever here in Santa Barbara during 1995. That was the year the first landslide/mudslide hit the very small beachside town of La Conchita, just 15 miles south of Santa Barbara. Completely destroying 9 homes with no major injuries. People continued living there, thinking it probably wouldn’t happen again. Then tragically in 2005, it happened again. Destroying about 13 more homes, damaging 23 others, and Killing 10 people. People still live there but have an advanced warning system in place. Link below if you or anyone would like to read about it.

http://en.wikipedia.org/wiki/2005_La_Conchita_landslide

First attached image is a hovmoller/composite using University at Albany maps of the 84-138 hour forecast for precipitation and 850-hPa wind anomalies, along with the 84-138 hour forecast for 850-hPa winds and absolute vorticity. The forecast suggests that starting around July 22 through early July 25, a short but moderate+ bout of westerly wind will occur near 140E-150E. Also, out in front of these winds, trades will be almost totally collapsed all the way up to the dateline and maybe slightly beyond. This will help add fuel in the form of more warm water to what appears to be a new downwelling phase. Initiated by the weak mini WWB we had near the end of June through early July. Enhanced trades have recently been blowing in and around the dateline area, but appear to be starting to weaken. Weak westerly anomalies have been present in the far Western Pacific for the last several days now. Due to a mixture of a weak active phase of the MJO and the very outer edge of the wind field produced by Typhoon Matmo. Weak high pressure looks like it will develop S-SSE of Matmo, but only briefly.

Second attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site, updated  July 19. Daily SOI values appear to be creeping lower and lower again. The 30 day avg has risen slightly. GFS forecast models are suggesting that by Monday(or sooner), daily SOI values are to become negative again, and continue through at least the end of next week. If this were to occur, the 30 day avg would VERY likely drop below -8. The SOI 30 day avg has been weakly negative for almost 3 weeks now and is likely to continue negative for possibly the next several weeks. The atmosphere may be showing weak signs of response. The low SOI values forecast for next week appear to be associated with something other than the MJO or a low pressure system passing to the south of Tahiti. The run of negative values for the 30 day avg is no where near El Nino, but it does suggest an unstable atmosphere. This is good for continued westerly winds and collapsed/weak trades. Of concern would be the cool upwelling phase throwing off whatever relationship the atmosphere and ocean may be trying to form. We shall see.
« Last Edit: July 31, 2014, 05:22:00 AM by bigB »

bigB

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Re: 2014 El Nino?
« Reply #1310 on: July 20, 2014, 01:02:43 AM »
Since ASLR is traveling, I will provide the ECMF(top image) and NCEP GEFS(bottom image) phase plots of the MJO index forecasts, updated July 19. Both are in fairly good agreement, suggesting the weak active phase will meander around the Maritime continents and far Western pacific for the next several days.

bigB

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Re: 2014 El Nino?
« Reply #1311 on: July 20, 2014, 04:22:55 AM »
Attached is the University at Albany maps of the 96 hour forecast for 850-hPa winds and absolute vorticity(top) along with the 96 hour forecast for precipitation and 850-hPa wind anomalies(bottom). The latest model run suggests the possibility of even stronger westerly winds than the last 2 or 3 runs. The GFS models now suggests winds in the 7-9 M/S-1 range, Which would qualify as a legit WWB. HOWEVER, this is (a) just a forecast and (b) the fetch(fetch is basically the area/distance in which constant wind blows over) is relatively small. So strong wind over small area. The size of the fetch is extremely important to how much warm water downwells. To put the importance of fetch size into perspective: Some of the biggest waves in the world(lets say open ocean swell of 35-45 ft with a 20-25 second period interval which would end up as waves with 65-85 ft faces once they broke) are created by storms with wind speeds of only 60 KT but over a large fetch. Meaning, 60 KT wind over a large fetch would transfer more energy to the oceans surface through friction than a category 5 hurricane with 140 KT winds speeds. This is due to the size of the fetch. Winter storms in the North Pacific can be as large as 1,000-1,500 miles wide, although only a portion of the fetch would be aimed in any given direction at any given time. Anyways, a large hurricane is about 450 miles wide or a third the size of a North Pacific winter storm. Just to clarify, even though a hurricane may have winds of 140 KT, a Large winter Storm with only 60 KT winds would create larger surf due to the larger fetch size and more wind energy transferred to the oceans surface through friction. There are other factors that come in to play as well, but we are only concerned with fetch here. I guess captured fetch would be important to point out as well. Captured fetch, is when constant wind blowing over an area blows in your general direction while at the same time the source of that wind(usually a storm) moves towards your direction. The reason I brought this up is because it appears the strong westerly winds currently being forecast are projected to be blowing over a very small fetch while moving slowly in the opposite direction most beneficial to us(propagating west rather than east). This will still help us though, but if the winds were the same strength and the fetch was 3 time as long, we would see some solid downwelling. It will be interesting to see how this plays out.
« Last Edit: July 31, 2014, 05:22:31 AM by bigB »

AbruptSLR

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Re: 2014 El Nino?
« Reply #1312 on: July 20, 2014, 06:53:07 AM »
I would like to note that the ECMF MJO forecast (posted by bigB) is different than the ECMM forecast issued July 19 2014, which is more bullish for a somewhat strong MJO entering the Western Equatorial Pacific, as indicated by the first attached image.


The second attached image by the BoM on July 20 2014 (Sydney time) for the 30-day moving average SOI indicates a -5.2 value (which in neutral):
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1313 on: July 20, 2014, 04:45:49 PM »
The attached MJO plots were all issued July 20 2014.  As can be seen by the first NOAA plot of the historical record, the active phase of the MJO has remained in the eastern portion of the Maritime Continent where it is gaining strength, as indicated by the second attached image of the ECMM MJO forecast, which is more bullish than yesterday's forecast.

Nevertheless, the third attached image of the GFS forecast is not bullish w.r.t. the active phase of the MJO.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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bigB

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Re: 2014 El Nino?
« Reply #1314 on: July 20, 2014, 09:51:23 PM »
Attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site. As of July 20, the SOI values are as follows: the daily value was up some at +3.02, the 30 day avg was also up some at -5.76, and the 90 day avg was down just slightly at +1.45. GFS forecast models for SLP at Darwin and Tahiti have backed off a little since yesterday, but still suggest that for the next 5 days or so, daily SOI values should stay near dead neutral if not slightly negative. Under this scenario the 30 day avg would basically remain around what it currently is for the next 5 days. If daily values continue slightly positive, the 30 day avg would continue slowly rising. If daily values become slightly negative, the 30 day avg would slowly fall.

ASLR,

I only have a basic understanding of MJO phase diagrams, but I believe the ECMM MJO forecast will always be a bit bullish as model based climatology is used to make the forecasts. The climatology used comes from model hindcasts rather than observations(though i couldn't tell you exactly why this makes the ECMM bullish, i do know this is what makes it bullish). The ECMF MJO forecast i posted yesterday and the ECMM MJO forecast you usually post, come from the same agency(ECMWF). The only difference is, one version(ECMM) uses model based climatology while the other(ECMF) does not. If you look at the two phase diagrams, you will see that ECMM forecast is essentially(but not exactly) just an exaggerated version of the forecast suggested by the ECMF. So the ECMM and ECMF suggests similar forecast trends, but the ECMM provides a more extreme version of the possible forecast tend. The ECMF(European) and NCEP GEFS(American) phase plots use the same methodology to create the MJO forecast. Since both do not use model based climatology, that would be the best way to see which has better skill. This would be because they are using the same available data.


bigB

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Re: 2014 El Nino?
« Reply #1315 on: July 20, 2014, 10:44:57 PM »
ASLR,

Or i suppose an even better test of MJO forecast skill, would be to compare the ECMM with the ECMF to figure out which methodology used to create each phase diagram is more accurate. Since one uses model based climatology, while the other does NOT, and they both come from the same agency/center(ECMWF).

bigB

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Re: 2014 El Nino?
« Reply #1316 on: July 21, 2014, 12:41:32 AM »
Attached is the 30-day time/longitude plot of zonal wind anomalies between 5N-5S, updated July 20. The forecast is still calling for a moderate to strong burst of westerly wind on the equator near 140E-150E. However, the forecast still suggests this will occur over a very small fetch and will be moving west(as it appears the source will be a single a tropical system) rather than east or even stationary. Note: Some of the more effective WWB appear to move east due to the active phase of the MJO or an atmospheric CCKW propagating east, leaving TC activity and/or westerly wind in their wake. Solely based on its potential strength, we should see some moderate downwelling. This image is a good example and should help clarify the importance of fetch size. The models do suggest a slightly larger fetch than yesterday but  still not ideal. The reality is that at this point, any westerly wind of this strength is welcome. Its also interesting to see how the TAO data still shows the warm subsurface pool in the Eastern Equatorial Pacific holding on at roughly +3 deg c. Although it is shrinking. Other subsurface data suggests cool water(besides whats currently seen in the Central Pacific) is trying to push through the shrinking Eastern Pacific warm pool and may soon make itself known off Ecuador and Peru. All the models suggest this cool water is pretty weak though. This is a critical time in the evolution of this possible El Nino event and I find it surprising that some people have stopped following or seem to have lost interest in monitoring its progress. We can say with almost absolute certainty that a Strong El Nino is not gonna happen this year, but the chances for a weak-moderate or moderate El Nino are still there. I suspect that if a new development occurs(new EKW), this thread will become active again. I must admit, I kind of miss all the activity and excitement that was found here just a few months ago...

bigB

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Re: 2014 El Nino?
« Reply #1317 on: July 21, 2014, 03:04:08 AM »
Attached is the University of Albany maps of the 180 hour forecast for 850-hPa winds and absolute vorticity, updated July 20. Just posting this image as its quite interesting to see that the GFS 180 hr forecast models suggest that what looks like a “conga line” of low pressure systems, will develop about 180 hours out. It doesn’t appear that they will be providing or aiding in a WWB at this point in time, but it may help keep trades week. Except for the high pressure system around 145E, 10N. Also, the latest run suggests that the possible WWB forecast to start up around Tuesday, may possibly involve two TC's now. This would be good. Notice in the northern hemisphere, there are 6 visible areas of low pressure between 110E-165W and 0-30N. That many low pressure systems(although some are weak) in such a confined area is not all that common, if it were to occur. Maybe lending credence to the theory proposed by ASLR and the ECMM phase diagram that a moderate active phase of the MJO may be about the move into the Western Pacific and beyond. Since this is all pretty much speculation, I wont post anything else on this possible westerly wind event until it actually begins to unfold.

AbruptSLR

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Re: 2014 El Nino?
« Reply #1318 on: July 21, 2014, 03:38:07 AM »
bigB,

Thanks for your discussion about the MJO forecasts, even though I was aware of all of the points that you made (and I concur with them all), many readers may not understand that not all MJO forecasts are the same.  Furthermore, I would like to note to all readers, that when I refer to "skill" this is a technical term that can be measured by tests and refers to the accuracy of the model predictions, and that I am in no way referring to the personal abilities of any researchers, or agencies, whether American, or European, when I am discussing the "skill" of the various MJO forecasts.  That said, I have eyeballed (not tested numerically) at least 18 different forecasts over the past 4 months, and it is my non-expert opinion that the ECMM forecasts have been consistently more accurate than any of the other approximately 18 model forecasts that I have eyeballed.

Obviously, various agencies around the world would not be running multiple MJO forecasts if such forecasting was a settled science with low uncertainty; therefore, I agree with bigB that it is speculative to consider that the active phase of the MJO might move towards the International Dateline with a meaningful level of strength, in a time frame when WWB is also active in this area (note that a strong MJO without WWB activity would likely have little impact on a new EKW).  Nevertheless, I believe that such an event is possible and probably represents the best chance that a moderate El Nino event might develop this year (I concur that a Super, or even a Strong, El Nino event is likely not in the cards this year).

Furthermore, as El Nino conditions tend to suppress MJO activity, the fact that the attached 30-day moving average SOI plot issued by the BoM on July 21 2014 is -5.9 (and indicates a neutral condition), this increases the possibility that the current active phase of the MJO cycle might possibily (say a 30% chance) trigger a new EKW within the next two to three weeks time:
« Last Edit: July 21, 2014, 04:08:41 PM by AbruptSLR »
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bigB

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Re: 2014 El Nino?
« Reply #1319 on: July 21, 2014, 05:20:12 AM »
ASLR,
 
I figured you might already be aware of methodology and variables that go into the MJO forecasts illustrated by the phase diagrams. In fact i almost opened my post with, "I'm sure you are probably already aware of this, but for those of you who don't know.....". I'm glad that you took the time explain "model forecast skill". As it is actually a very important factor to keep in mind, for those who are thinking about relying on or trusting in any type of forecast model for accuracy. Sometimes I forget that not every reader completely understands all the lingo, technical terms, acronyms, etc.. Then, at other times i feel like maybe I'm over explaining things to people who already know what I'm talking about. I'm guessing the readers are probably a mixture of both. So maybe its better to be safer than sorry. Anyways, I agree with everything you said. Very well put.

Thanks, bigB 

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Re: 2014 El Nino?
« Reply #1320 on: July 21, 2014, 05:56:22 AM »
The attached video is for those who would like to view the latest ENSO/MJO update/forecast video from STORMSURF.COM, by MARK SPONSLER updated July 20 2014. Skip to 8:45 to view ENSO/MJO update/forecast.

EDIT: Just wanted to note that the ENSO/MJO forecast update section in this forecast video is almost 20 minutes long, as Mark goes into a bit more depth and detail than usual. Hopefully, you are able to find the time. Enjoy...



« Last Edit: July 21, 2014, 06:15:39 AM by bigB »

AbruptSLR

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Re: 2014 El Nino?
« Reply #1321 on: July 21, 2014, 06:06:19 PM »
The first attached image shows the ECMM MJO forecast issued July 21 2014, which is even more bullish than yesterday.

The second attached image shows the GFS MJO forecast issued July 21 2014, which is slowly starting to converge towards the ECMM forecast, which is what one would expect if the ECMM forecast has more "skill".  We will see within a few days, to a week, whether the bullish trend continues (or not):
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2014 El Nino?
« Reply #1322 on: July 21, 2014, 07:43:41 PM »
The following linked reference demonstrates that the recent hiatus period can be projected by the CMIP5 projections, when the models are phased for ENSO.  This should allow such GCM projections to forecast the impact of a new phase of more frequent El Nino's associated with a positive phase of the IPO/PDO:

James S. Risbey, Stephan Lewandowsky, Clothilde Langlais, Didier P. Monselesan, Terence J. O’Kane & Naomi Oreskes, (2014), "Well-estimated global surface warming in climate projections selected for ENSO phase", Nature Climate Change, doi:10.1038/nclimate2310


http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2310.html

Abstract: "The question of how climate model projections have tracked the actual evolution of global mean surface air temperature is important in establishing the credibility of their projections. Some studies and the IPCC Fifth Assessment Report suggest that the recent 15-year period (1998–2012) provides evidence that models are overestimating current temperature evolution. Such comparisons are not evidence against model trends because they represent only one realization where the decadal natural variability component of the model climate is generally not in phase with observations. We present a more appropriate test of models where only those models with natural variability (represented by El Niño/Southern Oscillation) largely in phase with observations are selected from multi-model ensembles for comparison with observations. These tests show that climate models have provided good estimates of 15-year trends, including for recent periods and for Pacific spatial trend patterns."

See also:
http://www.theguardian.com/environment/climate-consensus-97-per-cent/2014/jul/21/realistic-climate-models-accurately-predicted-global-warming
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bigB

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Re: 2014 El Nino?
« Reply #1323 on: July 21, 2014, 08:13:59 PM »
Attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site. As of July 21, the SOI values are as follows: the daily value was down some at -0.68, the 30 day avg was down slightly at -5.96, and the 90 day avg was also down slightly at +1.39.

bigB

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Re: 2014 El Nino?
« Reply #1324 on: July 22, 2014, 01:46:53 AM »
Attached is the overview section of the CPC/NCEP MJO weekly update, issued July 21. The following link is provided for those who would like to view the full discussion.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjoupdate.pdf

AbruptSLR

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Re: 2014 El Nino?
« Reply #1325 on: July 22, 2014, 02:43:16 AM »
First, I provide the latest Nino Indices (for the week centered on July 16 2014) from NOAA below, indicating that the Nino3.4 has dropped to +0.2 (note that the Nino 4 has increased to +0.4):

                     Nino1+2       Nino3        Nino34        Nino4
 Week           SST SSTA   SST SSTA    SST SSTA   SST SSTA
 11JUN2014     24.6 1.6     27.3 0.8     28.1 0.4     29.5 0.6
 18JUN2014     24.8 2.1     27.4 1.0     28.1 0.5     29.4 0.5
 25JUN2014     24.0 1.6     27.2 1.0     28.0 0.5     29.3 0.5
 02JUL2014     23.6 1.4     27.0 1.0     27.8 0.4     29.1 0.3
 09JUL2014     23.0 1.1     26.5 0.6     27.6 0.3     29.1 0.3
 16JUL2014     23.1 1.5     26.2 0.6     27.4 0.2     29.1 0.4

Second, I provide the first attached image (from NOAA circa July 21 2014) of the Equatorial Upper-Ocean Heat Anomalies from 180 to 110W, which has now gone negative (indicating some local areas of upwell activity).

Third, I attach the BoM 30-day moving average plot issued July 22 2014 (Sydney Time) with the SOI drifting up from -5.9 yesterday to -5.8:
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1326 on: July 22, 2014, 04:47:56 PM »
All of the attached MJO plots (all issued on July 22 2014) are more bullish than yesterday for strengthening MJO in the coming days.  The first image is the historical record, the second the GFS forecast and the third the ECMM forecast:
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Re: 2014 El Nino?
« Reply #1327 on: July 22, 2014, 04:53:52 PM »
Per the attached plots of the Nino Indices by the BoM for the week ending July 20 2014, all indices are less bullish for El Nino conditions, which means that they are more bullish for an active MJO:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1328 on: July 22, 2014, 04:55:51 PM »
Here is BoM's Nino 4 for the week of July 20
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Re: 2014 El Nino?
« Reply #1329 on: July 22, 2014, 05:08:56 PM »
See attached, the July 17th subsurface temperature anomalies. You would barely even know there was a Kelvin wave threatening to start an El Niño with these kinds of readings. The cool, upwelling water is about to rise to the surface, then this chapter of the journey is over. Ostensibly, perhaps, based on the tenacity of NOAA's forecasts. Still, I'm moving my attention to the possible downwelling activity taking place 150 meters deep out west of the dateline. To be honest, I'm quite surprised CFSv2 is even still predicting a moderate El Niño, but perhaps they see something in this. I guess if MJO acts as aggressively as the forecasts are suggesting, things could change rapidly once more, towards El Niño.

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Re: 2014 El Nino?
« Reply #1330 on: July 22, 2014, 10:18:25 PM »
Attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site. As of July 22, the SOI values are as follows: the daily value was down at -8.00, the 30 day avg was down slightly at -6.08, and the 90 day avg was down slightly at +1.08. This suggests a weak active phase is currently over the Western Pacific. This is reflected by the latest observation points plotted on the MJO observation/forecast phase diagrams posted by ASLR. I suspect the SOI 30 day avg issued by the BOM will begin dropping as well, the latest daily value using their base period/method came out to -2.09(also a day or so behind). GFS models suggest that for the next 3-5 days, SOI values should continue falling. The last few model runs by the GFS, have begun entertaining the idea of a possible low pressure system passing to the south of a Tahiti. If this were to occur, then a more pronounced drop in SOI values would be seen. Models are also hinting that by early next week a less welcoming SLP pattern may take over. This is just a forecast and relies on the accuracy of weather forecast models.

Also, the strong westerly winds that models have been forecasting over the past few days, have begun as a new TC is trying to develop. Closer to the equator than what we have seen as of late. Models suggest  these westerly winds will continue for the next 72 hours or so with anomalies in the 8-9 M/S range. However, like the last several TC's that we have seen develop in the Western Pacific over the past 2-4 weeks, a high pressure system is forecast to develop to the SE of this possibly developing TC.  Meaning, easterly winds would follow closely behind, blowing over the same area as the westerly wind. The bit of good news is, around the same time, a patch of weak westerly wind anomalies is to be over or just East of the dateline.

Indeed, as has been mentioned by others, this upwelling phase appears to be gaining its grip. This is normal part of the Kelvin wave cycle and is typical of some years in which a weak-moderate or even moderate El Nino's have developed. It does not appear all that strong, especially considering the impressive strength of the downwelling phase that proceeded it. If the new weak downwelling phase currently seen in the Western Pacific does not continue developing/building over the next 2-4 weeks, then I will really begin worrying, as that would mean too much time has gone by. While cool water is pushing through, +3 deg c water remains. This should help slow down the cooling process. I do NOT doubt we will see some cooling occur. likely back to neutral. The current equatorial subsurface profile looks opposite of that seen in early Feb 2014. When cool SSTA were seen at the surface, while very warm subsurface temps were seen lurking beneath. Except the right now, the cool subsurface temps lurking beneath are not strong(but do cover a moderate size area). I suspect we'll know almost for certain, what the fate will be for 2014-2015 within the next 4-6 weeks. Possibly sooner...

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Re: 2014 El Nino?
« Reply #1331 on: July 23, 2014, 01:36:04 AM »
As indicated by deep octopus, the CFSv2 Nino3.4 forecast is still bullish for a moderate El Nino starting before mid-August as indicate by the attached forecast issued today:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Re: 2014 El Nino?
« Reply #1332 on: July 23, 2014, 02:33:16 AM »
The attached 30-day moving average SOI plot issued by the BoM on July 23 2014 indicates the index has fluctuated down to -6.4, and thus is still neutral:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

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Re: 2014 El Nino?
« Reply #1333 on: July 23, 2014, 03:22:51 AM »
To be honest, I'm quite surprised CFSv2 is even still predicting a moderate El Niño, but perhaps they see something in this. I guess if MJO acts as aggressively as the forecasts are suggesting, things could change rapidly once more, towards El Niño.
you and me both. 

perhaps we're still in the prediction phase where things aren't very clear yet, or perhaps the coupling in the Fall season (southern Spring) is stronger than now, and can push weak heat anomalies into a chained event... 

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Re: 2014 El Nino?
« Reply #1334 on: July 23, 2014, 04:09:48 AM »
Attached is the University at Albany maps of the latest analysis for 850-hPa winds and absolute vorticity, updated July 22. This shows strong actual westerly wind is current occurring on the equator between 140E-155E. Should last another 48 hours or longer before high pressure builds in. As mentioned previously, weaker west anomalies are still forecast to occur near the dateline from 84 hours through 132 hours, then neutral anomalies after that. Not bad.
« Last Edit: July 31, 2014, 05:24:01 AM by bigB »

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Re: 2014 El Nino?
« Reply #1335 on: July 23, 2014, 04:34:05 AM »
Attached is the TAO plot for 5-day EQ-depth temps/anomalies, Updated July 21. As we already know, cool water is pushing up on the last of the remaining subsurface warm pool. We should see a brief short lived warm up, over a very very small patch and not of any real help to the overall cause. Probably look more like a brief hot spot or flash. Then cool water is in control. The weak downwelling phase is going have to build to at least +2 deg C or maybe even +3 to be able to push through the denser cooler water now beginning to block its path.

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Re: 2014 El Nino?
« Reply #1336 on: July 23, 2014, 05:22:51 PM »
Sleepy,

I concur that this is interesting to follow now, as if even a weak El Nino gets started by the end of the boreal summer, 2014 will likely be the warmest year on record.

In this regards, the two attached MJO forecasts issued on July 23 2014, both indicate that the active phase of the MJO has strengthened from yesterday, and both are more bullish than they were yesterday for a strengthening MJO in the Western Equatorial Pacific.  The first attached image is of the GFS MJO forecast, which while more bullish than yesterday, still forecasts a weak MJO.  The second attached image is of the ECMM forecast which forecasts a MJO of reasonable strength as the active phase approaches the Dateline.

edit: Not to be repetitive, but it is my opinion that the ECMM forecast has more "skill" than the GFS forecast.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

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Re: 2014 El Nino?
« Reply #1337 on: July 23, 2014, 09:22:06 PM »
First attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site. As of July 23, the SOI values are as follows: the daily value was up at -1.85, the 30 day avg was up slightly at -5.75, and the 90 day avg was down slightly at +0.83. This is suggestive of a weak active phase of the MJO. Maybe ASLR can verify this, but I believe the reason the 30 avg has  gone up more than one would normally expect is because a moderate negative daily value of -11.5 on June 23, has left the 30 day time period. According to GFS models, we could possibly see a few moderate negative values enter the 30 day avg starting tomorrow and continuing through maybe Sunday. This would be due to a mixture of the active phase and a storm passing to the south of Tahiti. The only problem, moderate-strong daily SOI values will be leaving the 30 day time period at the same time as they're forecast to be entering in. This may cause the 30 day avg to drop slower than we would normally expect. If it all. Then a more unwelcome SLP pattern may enter the picture early-mid next week.

Second attachment is the 30-day time/longitude plot of zonal wind anomalies between 5N-5S, updated July 23. If there was such a thing as a “mini WWB”, this is probably what it would look like. According to this model, it appears these westerly winds will be the strongest we've seen since mid March, east of 140E and between 5N,5S. We did have a minimal WWB in April, but winds were a bit less strong. However,  they were over a much larger area and lasted much longer. Easterly anomalies are shown, but over a small area and half as strong. Notice the patch of weak westerly anomalies near the dateline.

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Re: 2014 El Nino?
« Reply #1338 on: July 23, 2014, 10:32:42 PM »
ASLR,

Please take a moment to look back at the GEFS and ECMM phase diagrams for the MJO forecast in your reply # 1317 and reply # 1325. The GEFS forecast was actually very acurate and close to reality, while the ECMM switched around a bit and was forecasting a moderate to almost strong MJO. However, I will absolutely agree with you that the ECMM seems to have a better long range(5-15 days out) forecast skill at most times, giving a better general idea of what the MJO might do. while i believe the forecast skill exhibited by the GEFS is better most of the time in the very short range (1-4 days out). Actually the GEFS picks up on the 1-4 day MJO pattern very well. Then the forecast skill becomes somewhat poor after that time. My only issue with the ECMM, its extremely bullish forecast for the strength of the MJO. It does look like the latest ECMM has backed off some though. I look at multiple Phase diagrams and find a mean. That seems to be the safest bet. The two years that i have been aware of phase diagrams, ive noticed sometimes one particular phase diagram does better than the other for a period of time and then it switches. So it seems safer to look at all of them and see which is doing better at that particular time with short, medium, long range forecasts. Then find a mean. This has been my experience with any weather forecast model that i have used on a regular basis over the past 20 years. Though i can swear climate change is messing with some of them :(. Maybe some of the models just need to update their base period. Anyways, Now I'm getting side tracked.

Thanks, bigB

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Re: 2014 El Nino?
« Reply #1339 on: July 23, 2014, 11:32:44 PM »
The attached image is from Stormsurf.com of the kelvin wave generation area wind speed and direction, which suggests that westerly winds up to 20-24 KT(10-12 M/S-1) are currently blowing on the equator inside the prime Kelvin wave generation area between roughly 145E to almost 160E. Provided is a link to this particular model which was created by Mark Sponsler of Stormsurf.com. The last time i provided a link, the model had just been created and was more of a Beta version. 

http://www.stormsurfing.com/cgi/display_alt.cgi?a=wwb_slp   


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Re: 2014 El Nino?
« Reply #1340 on: July 23, 2014, 11:36:32 PM »
bigB,

Thanks for your comments on the GFS, and the ECMM, MJO forecasts.  I cannot disagree with what you say, and I do not want to get expectations too high that a strong MJO will occur around the Dateline this cycle of the active phase, at the same time as a WWB; nevertheless, within a week or two or three, we will know what actually happens during this critical time period (for an El Nino to happen this year).  Also, I agree that forecasting is becoming harder, and I admit that my opinion (about the skill of the ECMM to project whether the active phase of the MJO will approach the Dateline with some strength, this cycle) is no better than anyone else's opinions on this matter.

Best,
ASLR
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1341 on: July 24, 2014, 02:31:31 AM »
The BoM SOI plot has not yet be updated, but nevertheless, the 30-day moving average has fluctuated up from -6.4 yesterday to -6.3 today (see below):

20140623,20140722,-6.3

edit: here is the plot
« Last Edit: July 24, 2014, 03:40:29 AM by AbruptSLR »
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― Leon C. Megginson

bigB

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Re: 2014 El Nino?
« Reply #1342 on: July 24, 2014, 03:29:20 AM »
Attached is TAO plots for 5-day EQ-depth temps/anomalies, Updated July 22. I guess the remaining warm subsurface water has finally been pushed up to the surface and the brief flash in SSTA has happened. This could possibly be a glitch or the warm +3 deg c anomalies dissipated over night. That was fast. I expected maybe this would happen over the next few days. Kind of a depressing sight, although somewhat expected. The TAO site does say that accidental/intentional contact with the TAO buoy lines by boats or fishermen does happen, throwing off the data, but this is probably actuality given the current conditions. The need for a new Kelvin wave is now desperate.

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Re: 2014 El Nino?
« Reply #1343 on: July 24, 2014, 03:56:25 AM »
The westerly winds north of Papua New Guinea at about 140E to 160E show nicely on CIMSS total precipitable water imagery.

http://tropic.ssec.wisc.edu/real-time/mimic-tpw/wpac/main.html


Can it overcome the cold east to west current?



We will see I guess.  I feel like I'm watching a sporting event where the team I'm pulling for is losing a tight game, but there's time for a comeback.

http://www.cpc.ncep.noaa.gov/products/GODAS/






« Last Edit: July 24, 2014, 04:06:00 AM by JayW »
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Re: 2014 El Nino?
« Reply #1344 on: July 24, 2014, 04:27:24 AM »
Attached is the EMC/MMAB High Resolution RTG SSTA image updated, July 23. Cool water is sure making itself known. It appears the far Western Equatorial Pacific has cooled quite a bit as well in the last week or so. Likely due to the all the recent TC activity causing local upwelling. Also, the recent westerly wind activity seems to be a likely factor. It looks like there's still a small building area warm SSTA west of the dateline, which seem likely associated with a building downwelling phase.

JayW,

HaHaHa, that's so true. I like the animations!

AbruptSLR

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Re: 2014 El Nino?
« Reply #1345 on: July 24, 2014, 04:44:57 PM »
One possible reason that the CFSv2 Nino3.4 forecast is still relatively bullish for a moderate (to weak) El Nino event this year (besides the uncertain combination of a reasonable strong MJO  near the Dateline, combined with a reasonable WWB, sometime after July 30 2014), is indicated by the attached earth surface wind map from July 24 2014, that indicates that a South Pacific Convergence Zone, SPCZ (see Replies #249 and #255), may be forming in the South Pacific which would support both cloud cover near the Dateline and increased frequency of WWBs (both of which are required to change the Walker Cell pattern).
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1346 on: July 24, 2014, 05:15:41 PM »
As both the ECMM, and the GFS, forecasts are late in being posted today, I provide the attached Wheeler & Hendon plot showing the 40-day record of the MJO through July 23 2014; which clearly indicates that the active phase of the MJO on the 23rd followed the ECMM forecast more actually than the GFS forecast (at the one-day period of forecasting, note that "skill" tests can be established to measure many different aspects of any given model forecast, say one-day, one-week, or other accuracy parameters).  With the MJO strengthening and moving westward, this will buy more time to develop a possible SPCZ and a WBB, and cloud cover over the Dateline sometime after July 30 2014.

edit:  The UK Met Office provides the following notice which may explain the tardy MJO forecasts (given that they are changing their format tomorrow):
"Please Note: The UK Met Office has changed their operational global model configuration and strategy. Included in this change are format changes to data displayed on this page. Figures using the new datasets along with documentation listing the changes are expected to be available by COB 7/25."
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AbruptSLR

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Re: 2014 El Nino?
« Reply #1347 on: July 24, 2014, 08:17:04 PM »
First,  the linked Long Paddock Station daily SOI data makes it clear that the BoM 30-day moving average will be becoming less negative in the coming days (which is a promising indication that the MJO may continue to strengthen in the coming days):

http://www.longpaddock.qld.gov.au/seasonalclimateoutlook/southernoscillationindex/30daysoivalues/

Second, the attached image of the NOAA SSTA for July 24 2014 indicates that while the current EKW is dissipating rapidly, the Equatorial Pacific is primed for a possible new EKW (should the atmospheric conditions support such a new EKW):
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

bigB

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Re: 2014 El Nino?
« Reply #1348 on: July 24, 2014, 08:48:53 PM »
First attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site. As of July 24, the SOI values are as follows: the daily value was -0.12, the 30 day avg was -5.55, and the 90 day avg was +0.67. Overall, this suggests neutral(but towards the low end of neutral) atmospheric conditions with a slight influence from a weak active phase of the MJO. As of this morning, a low pressure system was located to the SW of Tahiti. According to GFS models, this low pressure system will be passing to  the south of Tahiti during the next few days while it moves eastward. As it passes south of Tahiti, its expected to lower SLP in the region surrounding Tahiti. This should help replace some of the strong negative daily SOI values(from June 25-June 28) that will be leaving the 30 day avg over the next few days. Therefore, I suspect we wont see too much change, one way or the other, in values for the 30 day avg over the next few days(unless new negatives values are stronger). This is just a forecast and relies on the accuracy of weather forecast models.
 

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Re: 2014 El Nino?
« Reply #1349 on: July 24, 2014, 09:43:42 PM »
The attached image is of the Surfline GFS 48 hr forecast for Sea Level Pressure (SLP) and precipitation. This shows the SPCZ that ASLR was referring to. I suspect as long as Low pressure is passing south of Tahiti along with SPCZ running over Tahiti, Daily SOI values will be low(these low daily values over the next few days could lower the 30 day avg, but I believe not by a whole lot. Since strong negative values will also be leaving the 30 day avg). However, models suggest the SPCZ will weaken and no longer be affecting Tahiti after Monday or Tuesday. This coincides with a the unfavorable SLP pattern forecast to take over early next week. According to the models, daily values are to become weak-moderately positive again.
« Last Edit: September 10, 2014, 11:52:21 PM by bigB »