2014 El Nino?

[AbruptSLR]

As bigB likes to post the Long Paddock daily SOI value (but has not done so yet), I provide the following partial table with a new daily value of -31, indicating that the BoM 30-day moving average should continue to drop for some more days:

[Michael Hauber]

More like a westerly wind burst has produced a cyclone, which according to the models will head north and take the westerlies away from the equator.

[Lord M Vader]

Now we have a tropical depression in WPAC! But as MH said, it's heading north and take the westerlies away However, it seems possible that depression will be at minimal tropical storm strength as it crosses 10N latitude...

Latest PMEL/TAO pic indicates also that the recent WWB has peaked...

//LMV

[Lord M Vader]

Now we have a tropical depression in WPAC! But as MH said, it's heading north and take the westerlies away However, it seems possible that depression will be at minimal tropical storm strength as it crosses 10N latitude...

Latest PMEL/TAO pic indicates also that the recent WWB has peaked...

However, this piece of text is from JTWC with regard of TD-Eight:

"TROPICAL DEPRESSION (TD) 08W (EIGHT), LOCATED APPROXIMATELY 309
NM SOUTH-SOUTHEAST OF ANDERSEN AFB, GUAM, HAS TRACKED WEST-
NORTHWESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A HIGHLY ELONGATED AND
SLOPPY LOW LEVEL CIRCULATION CENTER (LLCC) WITH FLARING DEEP
CONVECTION ALONG THE SOUTHERN FLANK. A 022226Z SSMIS MICROWAVE IMAGE
REVEALS A HIGHLY CHAOTIC LOW LEVEL STRUCTURE WHILE THE CONVECTION
CONTINUES TO FLARE ALONG THE SOUTHERN PERIPHERY AS A STRONG (25 TO
30 KNOTS) WESTERLY WIND BURST CONTINUES TO PERSIST TO THE SOUTH AS
NOTED IN A RECENT 022353Z ASCAT PASS."

//LMV

[AbruptSLR]

Per Cyclocane:

"TROPICAL DEPRESSION EIGHT  - Current Wind Speed: 30 knots - max predicted speed: 105 knots at July 6, 2014 11:00pm
AT 030000Z, TROPICAL DEPRESSION 08W (EIGHT) WAS LOCATED
NEAR 8.9N 146.8E, APPROXIMATELY 309 NM SOUTH-SOUTHEAST OF ANDERSEN
AFB, GUAM, AND HAD TRACKED WEST-NORTHWESTWARD AT 10 KNOTS OVER THE
PAST SIX HOURS."

However, as LMV has noted, and as indicated by the attached earthwind map of surface winds, TD-08W has already moved north of 10N and is not generating much of a WWB.

[AbruptSLR]

I provide the three attached MJO plots issued July 3 2014, with the first two (historical & forecast, respectively) by NOAA, and the second by the ECMM.  They all indicate that within a week the active phase of the MJO will return to the eastern portion of the Maritime Continent, and the ECMM shows the MJO continuing from there into the Western Equatorial Pacific with a moderate strength (this indicates that after July 17: if a WWB event occurs in the Western Equatorial Pacific, and there is sufficient cloud cover near the equatorial dateline, and if the SOI is sufficiently negative, then it is possible that the MJO could have a chance of changing the Walker Cell into an El Nino configuration).

[bigB]

 First attachment includes images from the University at Albany of latest analysis for 850-hPa winds and absolute vorticity(TOP), along with the JTWC forecast for track and intensity of tropical depression 8W(BOTTOM). Both were issued on July 3. The top image from the University of Albany shows that as of July 3 at 12:00 UTC, the TC is already being steered away from the equator by an area of high pressure to its south. Eventually the TC will get picked up by the jet and steered rapidly to the north. So any westerly winds of benefit have pretty much already occurred. The good news is, we had 8 days(June 24-July 1) of modest westerly winds leading up to the past day and a half(July 2-July 3) of strong westerly winds produced by the TC. That’s about 10 days of moderate strength westerly winds. The bottom image from the JTWC shows that the TC has been steadily moving away from the equator and will continue to do so before moving rapidly to the north in about 1-2 days. The area of high pressure is the real reason we are not getting as much beneficial westerly wind as we would normally see from a TC like this. High pressure rotates clockwise in the N. Hemisphere and since its positioned to the south of the TC and right on the equator, we are actually getting easterly wind on the equator just below the TC. Please refer to the top image in the first attachment for visual reference. 

Second attached image is from NOAA/NESDIS of SSTA in the Western Hemisphere updated July 3, which possibly suggests the latest run of weak westerly winds/anomalies may have been sufficient enough to push some of the warm surface water back towards the Eastern Pacific. This might also suggest that the equatorial counter current(flowing from west to east) has strengthened again after drastically weakening due to the easterly winds we had two weeks ago. This is good. However, don’t be fooled by what you see on the surface. On the subsurface, water temps are still weak. Therefor, we still need subsurface reinforcement, but that appears to be whats happening right now. 

Third attached image is the TAO plots for 5 day EQ-depth temps/anomalies updated July 2, which shows that the latest weak WWB has in fact driven weak downwelling of at least +1 deg c water. This suggests that some sort of reinforcement is on its way east. Also, notice the warm downwelling has weakened the cool pool that was actually building under the central pacific just over a week ago.

The fourth attached Image is of  the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site, which shows the SOI 30 day avg continues to drop. Although, while daily SOI values remain negative, they appear to be rising some. According to weather forecast models for SLP over Darwin and Tahiti, daily SOI values will hang around neutral territory for the next several days before taking a hard drop once again mid to late next week. I'd expect the 30 day avg to remain on the low end of neutral or at the very least neutral(+8 to -8),before finally dropping below neutral later next week. However, this is just a forecast and relies upon the accuracy of GFS weather forecast models. Which as of July 3, suggest we may see another active phase of the MJO build back in over the Maritime Continent and into the Western Pacific by late next week or early the following week. This is reflected in some of the phase diagrams posted above by ASLR. Of Note is another option suggested by the upper level EWP 40 day forecast model. It suggests more of a neutral MJO pattern. That wouldn't be a horrible option as it could suggest an atmospheric condition reflecting El Nino is beginning to take over while the MJO pattern falls into the background. Again, this is just what a forecast models says. We shall See....

[AbruptSLR]

Comparing the first attached image from NOAA of the Equatorial Subsurface Temperature Anomalies for June 27 2014, with that previously posted for the comparable data for June 22 2014, one sees that more warm water is moving eastward from the Western Equatorial Pacific.  This trend is confirmed by the second attached image of the Equatorial Upper-Ocean Heat Anomalies circa July 3 2014; which indicates that for about the past week the heat anomalies have been stable.

[bigB]

ASLR,

Although upper ocean heat anomalies appear to have stabilized, they are still quite weak. +0.1 deg c anomalies are not sufficient enough to provide the atmosphere with the necessary heat needed to effectively sustain any possible feedback loop that may or may not be trying to develop. Therefore, I believe subsurface reinforcement is needed and that is exactly what appears to be happening right now, as mentioned by both of us in the previous posts.

[AbruptSLR]

The BoM has not yet updated their plot, so below I am providing the most recent 30-day moving average SOI values, indicating a most recent value of -5.3 (which while still neutral is getting closer to the El Nino supporting range below -8)

20140529,20140627,1.5
20140530,20140628,1.5
20140531,20140629,0.1
20140601,20140630,-1.5
20140602,20140701,-3.8
20140603,20140702,-5.3

[Lord M Vader]

The TC is forecasted to strengthen significantly the next couple of days and be a Cat 4 by monday. I won't be surprised if it may reach Cat 5 before that... By wednesday it should reach the southern part of Japan as a major hurricane.

Somewhat OT, but my main question for now is the current situation concerning El Niño. Given that there still are so big warm anomalies in the WPAC an the atmosphere reacting so slow; is there a possibilty that all this extra heat in WPAC takes so long time to being redirected to eastern pacific that we won't see the "real" El Niño showing up until early 2015? E.g that we get an El Niño not peaking until winter 2015/2016... After all, there are new times right now.

However, I do concur with ASLR that the current WWB have kicked off a new Kelvin wave. THe last days the anomalies in WPAC around 170W have switched to positive values. Let's see how things evolves the next couple of weeks..

//LMV

[Michael Hauber]

Most ENSO events peak around January, so if it forms late it is likely to be weak.  One exception was 86/87/88 which was weak in the first year but in the second year instead of collapsing it continued to build.

I've also noticed that many ENSO events tend to build in the 2nd and 4th quarters of the year.  The first quarter is when the last ENSO event dies, and often there is a pause roughly in the 3rd quarter until the ENSO event has another late burst for a Dec or Jan peak.

[AbruptSLR]

The first three attached images (all issued on July 4 2014) all show that the active phase of the MJO is on track to move to the Maritime Continent and strengthen there (the first two images are from NOAA with the historical and forecast MJO, respectively, and the third image is the ECMM forecast for the MJO).

The forth image is the last few daily readings of the Long Paddock station daily SOI readings, showing that the drop in SOI values will either slow, stall, or reverse soon, and thus the 30-day moving average is likely to remain neutral for the next several days.

[bigB]

 Attached image is Surfline.com's GFS 156 hr forecast for Sea Level Pressure (SLP) and precipitation, which suggests that around Thursday July 10, we will see another solid drop in daily SOI values. For now, we should see daily SOI values bounce around in the neutral range, keeping the SOI 30 day avg from rising too much. Then by mid next week, if the forecast holds true, we should see the SOI 30 day avg drop below the neutral range(below -8). However, this is just a forecast and relies on the accuracy of weather forecast models. Of Note: Once the SOI 30 day avg drops to near or below -8, it would then have to hold there for several months in row before one could officially declare that the SOI is reflecting El Nino atmospheric conditions. Rather than the MJO or other random weather events.

Just as i was about to post the SOI values from the Long Paddock sit i saw that ASLR had already done so. Adding onto what ASLR stated regarding the SOI, I will say this: Daily SOI values have risen and are now slightly positive. However, slightly positive daily values will only slightly raise the SOI 30 day avg. Therefore, the SOI 30 day avg should remain negative for the next several days. 

[bigB]

Attached image is a composite using Surfline.com GFS 168 hr forecast for Sea Level Pressure (SLP) and precipitation. Top image is the168 hr(July 11) forecast for SLP at Darwin, bottom image is the 168 hr(July 11) forecast for SLP at Tahiti. Just wanted to provide an easier on the eyes close up view of the GFS forecast for SLP at Darwin and Tahiti. Looking at the image, one can see the significant difference between SLP at Darwin and SLP at Tahiti. At first glance, it appears this would be due to a low pressure system moving over Tahiti. Taking a second look, one can see that this area of low pressure is actually quite weak and is embedded in a much broader area of low SLP. This is suggestive that something other than just an area of low pressure will be in play here. Likely due to the fact that GFS weather forecast models are calling for another pulse of the active phase of the MJO to move into the Western Pacific mid to late next week. Note: This is just a forecast and relies on the accuracy of weather forecast models.

[AbruptSLR]

First,  Based on its recent track record I would say that the ECMM forecasts represent as high of skill-level in forecasting MJO behavior as any in the world; and as the first attached image of the ECMM MJO forecast through July 19 2014 indicates that the active phase of the MJO may be gathering strength in the Western Equatorial Pacific in the third week in July; this could indicate increasingly positive atmospheric conditions for an El Nino event this year.  The second image of the GFS MJO forecast indicates comparable (but less favorable for an El Nino) conditions as the ECMM forecast towards the end of July.

Second, the attached third attached image of the 30-day moving average SOI plot by the BoM on July 5 2014, indicates that this index has fluctuated up to -5.1 and is thus still neutral.

[bigB]

First attached image is a composite using OSCAR plots for 5 day ocean surface current anomalies. The images are from July 2(TOP), June 2(CENTER), and May 7(BOTTOM). Looking at the composite, one can see that the Equatorial Counter Current(ECC) was tracking in a favorable El Nino configuration during early May through early June. That is, the ECC was tracking from west to east. Helping push warm surface water from the Western Equatorial Pacific to the Eastern Equatorial Pacific. Where it piles up(allowing only a trickle of warm surface water to flow back to the west). During mid June when we had that bout of easterly wind, the ECC began tracking anomalously from east to west. This may be a BIG part of the reason we saw that burst of warm SSTA in mid-late June. As the ECC flipped, it would have allowed the warm surface water that it had been piling up in the Eastern Pacific to rapidly rush back to the west(like releasing the flood gates). Now, looking at the top image in the composite, one can see that as of July 2, the ECC was still pushing hard, anomalously east to west(NOT GOOD). This suggests that the weak WWB we just had(June 24-July 4) may not have been sufficient enough to flip the ECC back into an El Nino configuration as it was hoped for(during El Nino the ECC pushes anomalously west to east). This is NOT something we want to see continue for much longer. As it would quickly drain the Eastern Pacific warm pool which is currently fighting to get re-established. This latest bout of westerly winds did however seem strong enough to at least temporarily stabilize the warm pool. But with easterly anomalies currently in play and expected to continue for the next several days, its something we need to watch. We need westerly anomalies to return ASAP and the good news is that as of right now westerly anomalies are in the forecast for late next week. (side note: TAO data continues to suggest weak downwelling(mini Kelvin wave) of + 1 deg c anomalies are currently heading east to reinforce the Eastern Pacific warm pool). The latest NOAA OSPO imagery, updated July 3, had lead me to believe that maybe the ECC had flipped or was flipping back to an El Nino configuration because it suggested SSTA had continued to increase in both temp and coverage. Strangely, other recent SSTA models suggested that if anything, SSTA had begun to slowly loose ground. So I'm not quite sure what that’s about. What I do know, the ECC is currently tracking unfavorably from east to west. Hopefully, this current round of easterly wind stays weak while the westerly winds forecast for next week are strong, flipping the ECC back to an El Nino configuration.

Second attached image is the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site, which shows weak positive daily SOI values are slowly raising the SOI 30 day avg. Still negative, but still neutral(+8 to -8).

EDIT: In the ocean surface current composite below, the darker the ORANGES and REDS, the stronger the anomalies. The RED arrows mean anomalies are tracking west to east(supporting El Nino), the BLUE arrows mean anomalies are tracking east to west(NOT supportive of El Nino).

[AbruptSLR]

The attached NOAA SSTA for July 3 2014 shows some cool surface water pockets near the Equatorial Pacific International Dateline; in the next week or two, we will see whether there, or not, the recent WWB can push some warm water from the western warm water pool, eastward into this area which is critical to warm if the Walker Cell is going to transition into an El Nino pattern this summer:

[AbruptSLR]

Per the BoM's plot of the 30-day moving average SOI issued July 6 2014, the index value has fluctuated up to -3.5, and thus remains neutral:

[AbruptSLR]

The ECMM MJO forecast issued July 6 2014, shown in the first attached plot, is much more bullish on the formation of a strong MJO active phase in the Western Equatorial Pacific by the third week in July than is NOAA's GFS MJO forecast also issued on July 6 2014, shown in the second attached image.  Due to the non-linear nature of the MJO it can be difficult to guesstimate which forecast is more correct (however, I will note that the European Centre has received higher funding streams than NOAA, for such forecasting, in recent years):

[bigB]

The attached image is of the recent (preliminary) southern oscillation index (SOI) values from the Long Paddock site, which shows relatively weak-modest positive SOI daily values continue slowly raising the SOI 30 day avg. Recently, GFS forecast models for SLP at Darwin and Tahiti seem to be a bit undecided on how things are going to play out next week. GFS models are still suggesting a weak low pressure system will pass to the south of Tahiti mid to late next week, but the models are now suggesting that SLP at Darwin may be a bit lower than previously forecast. We still seem to be on track for a drop in SOI values around mid to late next week, just maybe not as big of a drop. The GFS models have been doing fairly well with SLP forecast up to about 5 day out. So by tomorrow or Tuesday I suspect they will have a better handle on things.

[AbruptSLR]

As bigB indicated in the prior post the following 30-day moving average data issued by the BoM on July 7 2014 (Sydney Time) the SOI index has fluctuated up slightly and now has a value of
-3.4:

20140531,20140629,0.1
20140601,20140630,-1.5
20140602,20140701,-3.8
20140603,20140702,-5.3
20140604,20140703,-5.1
20140605,20140704,-3.5
20140606,20140705,-3.4

edit: attached is the associated plot

[bigB]

The attached video is for those who would like to view the latest ENSO/MJO update/forecast video from STORMSURF.COM, by MARK SPONSLER. Skip to 8:06 to view ENSO/MJO update/forecast.



http://youtu.be/rZpAbbY1tpM?t=8m6s

[AbruptSLR]

The following table of Nino indices was issued by NOAA today for weekly values centered on July 2 2014, indicating that the Nino3.4 has dropped below the El Nino threshold and is now +0.4:


                   Nino1+2       Nino3        Nino34        Nino4
 Week          SST SSTA    SST SSTA  SST SSTA   SST SSTA
02JUL2014     23.6 1.4     27.0 1.0     27.8 0.4     29.1 0.3

[AbruptSLR]

The first attached image from NOAA issued July 7 2014, shows that while the Eastern Pacific Equatorial Upper Ocean Heat Anomaly is close to zero, it also shows signs that it may have reached it's bottom (for this cycle), as indicated by how flat the trough is (indicating that heat is entering near 180 as fast as it is existing near 110W.

The second attached image issued by NOAA on July 7 2014 shows the Equatorial Pacific heat evolution indicating that another warm phase may be building in the Western Equatorial Pacific, ready to move eastward, to support an El Nino by the end of this summer.

[AbruptSLR]

The first image of the ECMM MJO forecast issued July 7 2014 continues to remain very bullish for a strengthening MJO by the third week in July; while the second attached image of the GFS MJO forecast, also issued July 7 2014, is much less bullish that a strong MJO will occur in the Western Equatorial Pacific later this month:

[AbruptSLR]

The linked reference discusses the relationship between WWBs and the available potential energy (APE) in the tropical Pacific Basin:

Hu, S., A. V. Fedorov, M. Lengaigne, and E. Guilyardi (2014), "The impact of westerly wind bursts on the diversity and predictability of El Niño events: An ocean energetics perspective", Geophys. Res. Lett., 41, doi:10.1002/2014GL059573.

http://onlinelibrary.wiley.com/doi/10.1002/2014GL059573/abstract

Abstract: "In this study, we apply ocean energetics as a diagnostic tool to investigate the impact of westerly wind bursts (WWBs) on the evolution, diversity, and predictability of El Niño events. Following Fedorov et al. (2014), we add an observed WWB to simulations within a comprehensive coupled model and explore changes in the available potential energy (APE) of the tropical Pacific basin. We find that WWB impacts strongly depend on the ocean initial state and can range from a Central Pacific (CP) to Eastern Pacific (EP) warming, which is closely reflected by the ocean energetics. Consequently, the APE can be used to quantify the diversity of El Niño events within this continuum—higher negative APE values typically correspond to EP events, lower values to CP events. We also find that a superimposed WWB enhances El Niño predictability even before the spring predictability barrier, if one uses the APE as a predictor."

[AbruptSLR]

While the plot has not yet been updated, per the following BoM data issued July 8 2014 (Sydney Time), the 30-day moving average SOI currently has a value of -3.3, and is thus still neutral:

20140607,20140706,-3.3

edit: for those who like to have the plot, here it is:

[bigB]

Adding on to an earlier post by ASLR. Attached are the 20°C isotherm depth and anomaly Hovmoeller plots from July 4, which suggest a relatively weak upwelling phase is pushing east while a new downwelling phase is trying to get started. Initiated by the weak westerly wind activity that we had from June 24 through July 4. Whats left of the warm pool in the Eastern Equatorial Pacific is holding off/weakening the leading edge of this upwelling phase as it pushes east. While at the Same time, the recent westerly wind event from June 24-July 4 has effectively kept the this upwelling phase from continuing to build. As long as trades stay weak and we get some sort of respectable westerly winds during the next 2-3 weeks, this upwelling phase is not of too much concern. Westerly wind would help build what looks like a newly developing downwelling phase of our next Kelvin wave. If westerly winds do not develop during July and easterly winds come back into play, this newly developing downwelling phase will go nowhere and the upwelling phase will build. However, that would be the worst case scenario an does not look likely. On another note, concerning the SOI. GFS weather forecast models have stabilized and suggest that around Thursday, SLP at Tahiti will be relatively low while SLP at Darwin is relatively high. This would help drop the SOI. Likely below -8, if it were to occur.   

[JayW]

The monthly ocean briefing for July is out.  I don't want to say too much, but it doesn't instill confidence that we will achieve an El Niño, in my opinion.  Dr. Wolter should update this week, it'll be interesting to see his take.

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

Monthly ocean briefing http://www.cpc.ncep.noaa.gov/products/GODAS/ocean_briefing_gif/global_ocean_monitoring_current.pdf

The overview

[AbruptSLR]

The attached three MJO plots were all issued on July 8 2014, with the first image showing the historical MJO track for clarity, the second image showing NOAA's GFS MJO forecast, and the third image showing the ECMM MJO forecast.  Again, the GFS forecast appears to be converging towards the ECMM forecast, which is still bullish about a strengthened MJO entering the Western Equatorial Pacific in the third week in July:

[AbruptSLR]

There is a major difference between NOAA's Nino3.4 value issued yesterday of + 0.4 (which indicate neutral conditions) and the attached BoM value for the week ending July 6 2014 of +0.53 (which indicates El Nino conditions).

[AbruptSLR]

Attached are BoM's Nino 1, 2, 3, and 4 indices (respectively) for the week ending July 6 2014:

[AbruptSLR]

The BoM 30-day moving average SOI issued July 9 2014 has drifted up to -3.2, per the attached plot:

[JayW]

Attached is the global tropics hazard and benefitts outlook map for the next 14 days.

I will just post the first paragraph.  Link http://www.cpc.ncep.noaa.gov/products/precip/CWlink/ghazards/

An incoherent subseasonal pattern of tropical convective and zonal wind anomalies contributed to weak signals on both the Wheeler-Hendon (RMM) and CPC MJO indices during the past week. The spatial pattern of upper-level velocity potential anomalies exhibited influences from higher frequency modes, such as tropical cyclone activity over the eastern Pacific and anomalous divergence over Africa. During the past several days, however, these conflicting signals have weakened. Additionally, constructive interference of a strong equatorial Rossby Wave (ERW) and a Kelvin Wave over the eastern Indian Ocean and Maritime Continent contributed to an ongoing large area of enhanced convection. The RMM Index has responded to this evolution and is currently projecting a signal in Phase-4.

[AbruptSLR]

As indicated by the information that JayW posted, the MJO is strengthening in the Maritime Continent as indicated in the first attached image.

The second attached image issued by the ECMM on July 9 2014 also bullish on the formation of a strong MJO in the coming week and the third attached image indicates that the GFS MJO forecast by NOAA is slowly coming into line with the ECMM MJO forecast

[wili]

SkS has a nice summary on the current situation just out: https://www.skepticalscience.com/El-Nino-in-2014-Still-on-the-way.html

[AbruptSLR]

wili,

Thanks for the link to the SKS article on the El Nino status.  Previously, I had noticed that warm ocean water was leaking southward from the Western Tropical Pacific, but I had never previously thought to link this leakage to the South Pacific subtropical gyre as indicated by the attached image (and associated caption) from the article:

Caption: "Global sea surface height (SSH) anomaly for May 2014. The black ellipses are a (very) rough sketch of the Pacific Ocean subtropical gyres, with the arrows denoting the direction of their rotation. Above-average SSH in the South Pacific gyre indicates warm water mass (exported from the tropics) piling up in the centre of the gyre, whereas below average SSH in the North Pacific indicates weaker-than-normal circulation. Units are in centimetres Image adapted from CPC GODAS."

[wili]

Glad it was useful for you. I found that an interesting analysis, too.

[deep octopus]

Thanks wili. I also enjoyed the read.

JTWC gives a low probability that a tropical disturbance at 7N, 154E will development into a cyclone in the next 24 hours.

http://www.cyclocane.com/tropical-storm-risk/#nwpac

   B. TROPICAL DISTURBANCE SUMMARY:
      (1) AN AREA OF CONVECTION HAS PERSISTED NEAR 7.3N 154.4E,
APPROXIMATELY 150 NM EAST OF CHUUK. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A BROAD AND ILL-DEFINED LOW-LEVEL CIRCULATION CENTER
WITH FLARING AND DISORGANIZED CONVECTION. A 082328Z ASCAT PASS SHOWS
A HIGHLY DISORGANIZED AND ELONGATED CIRCULATION WITH 10 TO 15 KNOT
WINDS. SEA SURFACE TEMPERATURES IN THE REGION ARE CONDUCIVE FOR
DEVELOPMENT. UPPER-LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT AS
HIGHLY DIFFLUENT OUTFLOW THAT IS BEING ENHANCED BY A TUTT CELL
LOCATED NORTHEAST OF THE SYSTEM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1010 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

[Michael Hauber]

Quite interesting to see another pair of lows NE of PNG already.  While we have had a lack of westerlies I've noticed that there have been strong tropical westerlies through the Indian ocean that have been bending north along the SE Asian coast and have hardly extended into the Pacific.  With the major typhoon near Japan I would expect this to get worse as the Indian westerlies are drawn towards the typhoon, and the typhoon draws in easterlies from the Pacific.  But this typhoon is not drawing any tropical air from the east, and isntead there is a pair of swirls near the equator,  causing westerly activity in the west Pacific.  This may be a sign the atmosphere is starting to respond with tropical activity in the western Pacific that will tend to create westerly winds.  There is quite a lot of warm water in this area at the moment, much more than typical for this stage of an El Nino - partly because the warm water hasn't been sent east as it normally would be.

[bigB]

The first three attachments are composites using OSCAR plots for 5 day ocean surface current anomalies(1st ATTACHMENT), TAO plots for 5 day depth temps/anomalies(2nd ATTACHMENT), and EC global SSTA and snow cover(3rd ATTACHMENT).  The images in all three composites compare oceanic anomalies from early June to early July. For the first time since this potential El Nino began to develop back in late January/early February, I'm actually starting to worry that it may be a bust. The chances of an El Nino developing in 2014 almost seem to be diminishing. Either this is just  the temporary passage of a weak upwelling phase(cool phase) before a new downwelling phase(warm phase) develops, or this El Nino is beginning to fail. If we don't get a WWB or at least a prolonged collapse in trades during the next 2-3 weeks, the possible newly developing downwelling phase of our next Kelvin wave will go nowhere, and ENSO-neutral conditions will likely continue through 2014. What happens during the rest of July and into very early august, will determine the fate of this year's potential El Nino event. There's still hope, but I have to admit, things are looking less promising.

I'm also re-posting the 20°C isotherm depth and anomaly Hovmoller plots from July 4, which shows the relatively weak upwelling phase(cool phase) is pushing east while a new downwelling phase(warm phase) is potentially trying to get started. If a WWB or a prolonged collapse in trades were to occur in the next 2-3 weeks then warm water would build and begin pushing east as our next Kelvin wave, saving our chances for El Nino this year

[bigB]

Unfortunately, looking at multiple weather forecast models, it appears that we will experience the same problem we did with last TC. A high pressure system is forecast to develop on the equator to the south-southeast of the TC, steering/keeping the TC away from the equator. That would possibly mean less westerly wind benefit and more problematic easterly winds on the equator. I hope this is not the case but this is what most forecast models seem to think will happen. We should get some beneficial westerly wind but not as much as we would like to see. This depends on the accuracy of weather forecast models so things could change. I have attached is the University at Albany map of the 126 hr forecast for precipitation and 850-hPa wind anomalies for visual reference. Oh and good see you're back JayW. I was wondering what happened to you.

[AbruptSLR]

Attached is the BoM 30-day moving average SOI issued July 10 2014, indicating that this index has drifted up to -1.7

[bigB]

The attached image from the University at Albany of the latest analysis(July 9) for precipitation and 850-hPa wind anomalies, which shows that weak-moderate westerly winds are currently occurring on the equator in the far Western Pacific(130E-140E) as mentioned by Michael Hauber. Unfortunately, they are only forecast to continue for the next 24-36 hrs before turning neutral and then easterly by 72 hrs.

ASLR,

Hopefully, the SOI will begin dropping as a low pressure system is currently on track to affect Tahiti by tomorrow afternoon through Saturday. Dropping SLP at Tahiti to as low as 1009 MB.

[AbruptSLR]

bigB,

While it is certainly possible that after about July 17 the 30-day moving average SOI may fall below -8, but the real question is whether it will stay there for a sustained period of time.

The first attached ECMM MJO forecast issued July 10 2014 is a little less bullish on the strength of the MJO as it travels east through the Western Equatorial Pacific after July 21, so much so that I think only a strong WWB in the Western Equatorial Pacific around the July 17 to 22 timeframe could help to transition the atmosphere into a more El Nino friendly pattern.

The second image of the GFS MJO forecast (issued July 10 2014) does not forecast the MJO to enter the Western Equatorial Pacific through July 24 2014.

Best,
ASLR

[BornFromTheVoid]

We have tropical depression 09W, sitting about 10N and slowly moving toward the Philippines.



http://www.usno.navy.mil/JTWC/

[bigB]

ASLR,

Yeah I see where you're coming from. As of right now, It appears that even if SOI values were to drop to below or near -8, they would not hold there for long. Weather forecast models are calling for a SLP pattern more suggestive of neutral conditions is to take over by early next week.

[bigB]

I know I'm repeating myself, but the attached image is from STORMSURF.COM of the GFS 42 hr forecast for Kelvin wave generation area wind speed and direction, which suggests a high pressure system will soon form on the equator to the south-southeast of the current TC. This will steer the current TC away from the equator and block most of the beneficial westerly wind from entering the prime Kelvin wave generation area. Also, with a high pressure system on the equator, we would see easterly wind. This is the same scenario that played out during the last TC. The actual TC itself, only gave us 3 days of beneficial westerly wind. This current TC is a much smaller system, which means its wind field is much smaller. We'll see, but it does not look good. I have marked the areas of high and low pressure to make it easier to see.

[AbruptSLR]

I concur with bigB that the tropical depression that BFTV identifies will be too far north before it gains sufficient strength to provide a proper WWB, and that when this tropical depression turns into a tropical cyclone, it will be trailed by a high pressure system that will pull-in easterlies into the Western Equatorial Pacific; which will kill the active phase of the MJO starting around July 16 and indicated by the attached Albany U surface wind and vorticity forecast for July 16: