2012 ENSO Thread

[aljareer]

QBO by : ECMWF :

http://www.lmd.polytechnique.fr/VORCORE/Previsions_eq.htm

Thanks to all .

[Entropy]

That ONI of only +0.1 looks very suspect to me. It should have come in near +0.5. I don't know the reason for this. The weeklies suggest near +0.5. I've never seen the weeklies and ONI anywhere near this far off. Actually, the last two ONI's look too low. AMJ and earlier look fine to me.

Looks to me like 2006-07 is a good match for current conditions. The ONI peaked at +1.1C on the 1971-2000 climatology (and +1.0C on the current 1981-2010 climatology). StormchaserChuck had a good post on the correlation between springtime MEI and eventual ONI peak back in 2006. He found (at the time) only seven years where there was a weak Mar-Apr MEI (nothing below -1.0 or above +1.0) that rose greater than +0.4 between Mar-Apr and Apr-May. The seven examples were 1957, 1965, 1972, 1982, 1986, 1997, and 2002. In all of those years, the ONI peaked at or above +1.5 during the wintertime. Based on the old 1971-2000 scale, 2006-07 was somewhat weaker than those years, but did peak at +1.1C or low-end moderate. It's worth noting, however, that the weekly ONI values have been higher than 2006-07 this year (although the tri-monthly has been slightly lower). On September 24, 2006, the weekly ONI was up to +0.8C. Already, as of August 31, 2012, the weekly ONI was up to +0.9C. Based on this, I now suspect a low-end moderate El Nino (peak ONI of +1.0-1.4C is the most likely result). I would go higher, but based on recent trends and the fact that 2006-07 seems to be the closest analog to this year, suspect a lower result is more likely.

As we can from this, there's still a nice warm pool underneath the surface. During 2006-07, the deep water warmed somewhat during the month of September. It will be interesting to see whether there is a repeat of this phenomenon this year.

Edit: Just to be clear, the same pattern Chuck detected during Spring 2006 occurred this year. The Mar-Apr MEI was +0.059, and the Apr-May MEI was +0.706 -- an increase of ~0.65. And even with the unusual MEI drop between Jun-Jul and Jul-Aug, the current conditions aren't far from what was present in 1994 or 2006 at this time.

[easternsnowman]

I believe the nino peaked early during the 2006-07 winter.If it was'nt for the sleet storms(one in Feb and one in March) I would of had at least average snow for the winter.

[Mike.Ventrice]

According to Paul Roundy's hovmollers, the overall atmospheric response to this year's ENSO is minimal. This is highlighted by the 200d low pass filtered OLR anomalies (Black contours). 1997 is also shown for direct comparison. In 2006, there was more of an atmospheric response than what we are observing in this ENSO. There is a continuum of ENSO events, trying to bin them into categories or make analogs to previous ENSO events, is a reciept for error.

[SoCoWx]

Looks to me like 2006-07 is a good match for current conditions. The ONI peaked at +1.1C on the 1971-2000 climatology (and +1.0C on the current 1981-2010 climatology). StormchaserChuck had a good post on the correlation between springtime MEI and eventual ONI peak back in 2006. He found (at the time) only seven years where there was a weak Mar-Apr MEI (nothing below -1.0 or above +1.0) that rose greater than +0.4 between Mar-Apr and Apr-May. The seven examples were 1957, 1965, 1972, 1982, 1986, 1997, and 2002. In all of those years, the ONI peaked at or above +1.5 during the wintertime. Based on the old 1971-2000 scale, 2006-07 was somewhat weaker than those years, but did peak at +1.1C or low-end moderate. It's worth noting, however, that the weekly ONI values have been higher than 2006-07 this year (although the tri-monthly has been slightly lower). On September 24, 2006, the weekly ONI was up to +0.8C. Already, as of August 31, 2012, the weekly ONI was up to +0.9C. Based on this, I now suspect a low-end moderate El Nino (peak ONI of +1.0-1.4C is the most likely result). I would go higher, but based on recent trends and the fact that 2006-07 seems to be the closest analog to this year, suspect a lower result is more likely.

As we can from this, there's still a nice warm pool underneath the surface. During 2006-07, the deep water warmed somewhat during the month of September. It will be interesting to see whether there is a repeat of this phenomenon this year.

Edit: Just to be clear, the same pattern Chuck detected during Spring 2006 occurred this year. The Mar-Apr MEI was +0.059, and the Apr-May MEI was +0.706 -- an increase of ~0.65. And even with the unusual MEI drop between Jun-Jul and Jul-Aug, the current conditions aren't far from what was present in 1994 or 2006 at this time.

I personally hope not. That winter was the same as this past Winter for those of us south of the Northeast. We missed the February storm. Never had any accumulating systems until Valentine's Day and even that was less than an inch. And we didn't get more than an inch of snow until the day before Easter in April.

Maybe it's just wishful thinking, but I'm banking on considerably more blocking than that year, which had none until Winter was almost over.

[SnowGoose69]

I personally hope not. That winter was the same as this past Winter for those of us south of the Northeast. We missed the February storm. Never had any accumulating systems until Valentine's Day and even that was less than an inch. And we didn't get more than an inch of snow until the day before Easter in April.

Maybe it's just wishful thinking, but I'm banking on considerably more blocking than that year, which had none until Winter was almost over.

The NAO was strongly positive though that winter and the AO even more positive than the NAO, its hard to say if it was negative how different the results would have been, if we get one or both indices negative with an otherwise similar setup to 06-07 it will likely work out alot differently.

[GaWx]

1) Evaluation of 8/22-31:

I did well. 8/22-31 all had +'s except that there was a small - on 8/29. August 2012 ended up being

-6.2 vs. my guess of ~-6. A -6 in August is pretty consistent with a weak Nino peak in fall/winter as opposed to a stronger one.

2) SOI Forecast for 9/1-10: pretty undramatic, which certainly doesn't support a moderate or stronger El Nino:

9/1: near 0

9/2-4: small -'s

9/5-10: small +'s peaking on 9/6-7 (maybe as high as low teens at peak)

1) Eval. of 9/1-10:

I did pretty well. It did peak on 9/6-7, but the peak of +14.32 was slightly higher than the low teens I expected plus the SOI almost came back to that peak on 9/9. The important thing is that 9/1-11 are averaging ~+6 and continue the idea that only a weak Nino is being supported.

2) SOI fcast 9/12-21:

9/12: small - (1st - in 8 days)

9/13: small -

9/14: near 0

9/15: small -

9/16: ~-11

9/17: smaller -

9/18: small +

9/19: ~0

9/20: small -

9/21: small -

So, I'm predicting that 9/12-21 will average out to be a small negative...maybe ~-4. So, as of 9/21, the MTD would still be averaging a small +..perhaps ~+1 to +2. So, SEP as a whole will likely come in with a small anomaly (+ or -). Bottom line: SOI even more solid support for a weak Nino over moderate or strong Nino, whose chances are dwindling. I have strong's as well as high end moderate's chances near 0. I have the chance for low end moderate (+1.1 to +1.2 fall/winter ONI peak) as low. I continue to predict a weak Nino fall/winter peak per ONI: i.e., no higher than +1.0 trimonthly peak.

[GaWx]

Folks,

This morning, I called CPC/NOAA and talked to them about the past two very low ONI #'s in relation to the weeklies. They are fully aware of the inconsistencies and are investigating. One of the problems is that the ONI is based on ERSST data, which comes from the NCDC in Asheville. OTOH, the weeklies are based on OISST data, a different dataset. They acknowledged that the ONI is deceivingly low vs. the weeklies and that they are curently basing their weekly Mon. updates mainly on the weeklies, not the ONI, because they feel that the weeklies are "much more reliable than the ONI" right now. One reason they don't just want to stop using ERSST is because it goes back so far in time...to the late 1800's and they actively use it going back to 1950. In contrast, the OISST data goes back only to 1980 for monthly and 1990 for weekly.

They are already in touch with the NCDC about the disconnect and feel it will take a good bit of time to diagnose the situation. They aren't even sure there actually is an actual data problem with ERSST as it may be a statistical/interpolation/rounding issue being the main cause. I plan to follow up with them in about a month.

[usedtobe]

Larry, I appreciate your contacting cpc and also your projections of ENSo.

[GaWx]

Larry, I appreciate your contacting cpc and also your projections of ENSo.

Wes,

You're welcome.

Folks,

I've decided to take the three month average of the weeklies and use that to approximate the "official" ONI until the ONI inconsistency issue itself, is resolved. This is a major change for me because I have been using the ONI table for the better part of ten years to determine "official" ENSO phases and NOAA has been using it for "official" determinations.

I am going with +0.3 for MJJ and +0.5 for JJA for the approximated ONI. My educated guess is that JAS will end up ~+0.7 based on the weeklies. In order for me to count this as a weak Nino instead of neutral positive, there will need to be at least five trimonths in a row of +0.5+ as per the NOAA requirement. With JAS, we'll have two. Barring something totally unforeseen, ASO will be the third. I'm confident based on the models as well as history that SON and OND will also be +0.5+...that would make it an official weak Nino as far as I'm concerned assuming none exceed +1.0 as I expect. Keep in mind that the weeklies can spike as high as ~+1.4 and still allow for no more than a +1.0 three month average based on the past. The latest weekly was +0.8, down from +0.9 a week earlier.

My decision is largely based on that telecon I had this morning with NOAA. They are pretty much now using the weeklies and ignoring the ONI and recommended I do the same.

[uncle W]

I wonder if the MEI is wrong also...It had the largest drop for a developing el nino in history...

[Ed Lizard]

Dumb questions 1) Google says ONI is an attempt to adjust for changes in climate as far as Nino area SST anomalies go. Does the ONI factor in all the Nino region SSTs?

2) My understanding, the MEI, factoring in six different tropical ocean indexes, is probably the most informative, but data is only available monthly, after the month in question has ended? Would a monthly MEI plot, although a little past its freshness date, be more informative?

Not a major ENSO guy, except for 1) tropics (and SOI values making me feel better about October) and 2) warm ENSOs are somewhat more likely to produce the rare South Texas snow events.

[GaWx]

Dumb questions 1) Google says ONI is an attempt to adjust for changes in climate as far as Nino area SST anomalies go. Does the ONI factor in all the Nino region SSTs?

I can answer #1. Not a dumb q. ONI factors in only region 3.4, the key region for official designations.

[GaWx]

By the way, the latest available JMA SST anomaly, which is based on MAMJJ, is a surpringly warm +0.6. I would have expected a cooler number since it is centered on May. Then again, the JMA region is not the 3.4 region. Regardless, if anything, that gives me even more confidence that the ONI table is out of whack.

ftp://www.coaps.fsu.edu/pub/JMA_SST_Index/jmasst1868-today.filter-5

[wxmx]

Constant anomalous easterlies have taken it's toll on the budding Niño. Reinforces the idea of a weak Niño. CFSv2 even thinks that it will peak very early (Oct/Nov)

[nflwxman]

Is there a chance of no el-niño whatsoever? Those graphics seem to suggest fizzling?

[SoCoWx]

Is there a chance of no el-niño whatsoever? Those graphics seem to suggest fizzling?

There's a chance, but I'd say chances of a weak El Nino are still decent right now.

[wxmx]

Constant anomalous easterlies have taken it's toll on the budding Niño. Reinforces the idea of a weak Niño. CFSv2 even thinks that it will peak very early (Oct/Nov)

Significant drop in the weeklies

 29AUG2012 20.3-0.2 25.6 0.7 27.7 0.9 29.1 0.5
05SEP2012 20.7 0.3 25.5 0.6 27.5 0.8 29.2 0.5
12SEP2012 20.9 0.5 25.3 0.4 27.3 0.5 29.1 0.4

plus...30 day SOI is positive, 850mb wind anomalies are still easterly in the short term and SSTAs cooled even more, with negative anomalies showing up around Niño 4 in the AVHRR map

OTOH, a moderate WWB is showing up in the CFS, with an MJO wave pushing these anomalies to the east around mid October with another push in early/mid Nov. Odds are still favoring a weak Niño peak, but neutral warm probabilities are going up.

[CoastalWx]

Regions 1 and 2 are slowly coming up..probably in the wake of that Kelvin wave and erly wind burst. It seems like we'll see some response over the next few weeks once this region of anomalous easterly winds goes away.

[OKpowdah]

Quasi-Biennial Oscillation (QBO) in Stratospheric Zonal Winds and Interannual Atlantic Hurricane Activity . by Gray 1984

2005 has issues with that.

[GaWx]

The 21.22 SOI for 9/20 has to be a mistake. That assumes that the Darwin 24 hour averaged pressure fell from 1012.50 to 1009.10 mb. That definitely didn't occur! The Darwin pressure was more like ~1012, which means that the daily SOI was really ~+4 rather than +21.22. This is based on looking at hourly SLP's as well as sfc weather maps. I often follow this day by day. This is a very rare error on their part. Hopefully, they'll fix it on their own. Nevertheless, I'll try to contact them.

http://www.longpaddo...30daysoivalues/

Edit: The 9/21 Darwin SLP will be released as ~1011.50-1012 mb assuming it is calculated correctly.

[GaWx]

The 21.22 SOI for 9/20 has to be a mistake. That assumes that the Darwin 24 hour averaged pressure fell from 1012.50 to 1009.10 mb. That definitely didn't occur! The Darwin pressure was more like ~1012, which means that the daily SOI was really ~+4 rather than +21.22. This is based on looking at hourly SLP's as well as sfc weather maps. I often follow this day by day. This is a very rare error on their part. Hopefully, they'll fix it on their own. Nevertheless, I'll try to contact them.

http://www.longpaddo...30daysoivalues/

Edit: The 9/21 Darwin SLP will be released as ~1011.50-1012 mb assuming it is calculated correctly.

As expected, the Darwin pressure for 9/21 (1012.5) was back to near where it was on 9/19 (actually the same). So, 9/21 appears to have been calculated correctly. The 9/20 Darwin pressure of 1009.10 is definitely wrong as I mentioned (based on the hour by hour readings, which I follow from day to day), thus causing the erroneous 9/20 SOI high blip of +21.22. Darwin should have been near 1012 mb, which would have meant an SOI near +4. Hopefully, it will eventually be corrected once they realize their error. If not, an erroneous blip will remain.

So, I'm assuming an SOI of +4 for 9/20 for my own purposes. So, I have +2.74 for 9/19, +4 for 9/20, and +6.18 for 9/21 as opposed to +2.74, +21.22, and +6.18.

[GaWx]

As expected, the Darwin pressure for 9/21 (1012.5) was back to near where it was on 9/19 (actually the same). So, 9/21 appears to have been calculated correctly. The 9/20 Darwin pressure of 1009.10 is definitely wrong as I mentioned (based on the hour by hour readings, which I follow from day to day), thus causing the erroneous 9/20 SOI high blip of +21.22. Darwin should have been near 1012 mb, which would have meant an SOI near +4. Hopefully, it will eventually be corrected once they realize their error. If not, an erroneous blip will remain.

So, I'm assuming an SOI of +4 for 9/20 for my own purposes. So, I have +2.74 for 9/19, +4 for 9/20, and +6.18 for 9/21 as opposed to +2.74, +21.22, and +6.18.

To illustrate to the reader why I'm 100% confident in saying that the 24 hour averaged reading for Darwin for 9/20 couldn't have been anywhere near 1009.10 (the diurnal lows barely got to that vicinity while the highs were near 1015 mb), here is a time sensitive link to the last 72 hours of half-hourly Darwin readings, including SLP in mb in the 3rd column from the right:

http://www.bom.gov.a...901.94120.shtml

If you average all of the readings from that 3rd column from the right, you will see that they don't vary much from day to day of the last 72 hours and they average near 1012-1012.5 mb on each of 9/19, 9/20, and 9/21.

[Entropy]

With the recent cooling going on along and west of the Date Line, it's starting to look like the El Nino will be more east-based than expected.

[SoCoWx]

With the recent cooling going on along and west of the Date Line, it's starting to look like the El Nino will be more east-based than expected.

The warm anomalies will migrate westward.

[GaWx]

As expected, the Darwin pressure for 9/21 (1012.5) was back to near where it was on 9/19 (actually the same). So, 9/21 appears to have been calculated correctly. The 9/20 Darwin pressure of 1009.10 is definitely wrong as I mentioned (based on the hour by hour readings, which I follow from day to day), thus causing the erroneous 9/20 SOI high blip of +21.22. Darwin should have been near 1012 mb, which would have meant an SOI near +4. Hopefully, it will eventually be corrected once they realize their error. If not, an erroneous blip will remain.

So, I'm assuming an SOI of +4 for 9/20 for my own purposes. So, I have +2.74 for 9/19, +4 for 9/20, and +6.18 for 9/21 as opposed to +2.74, +21.22, and +6.18.

I just got an email from the "Queensland Climate Change Centre of Excellence" in Australia (their workweek just began) stating that they see that there is an issue with the SOI data and that they are investigating. They also said they will let me know when the issue is resolved, and they thanked me for alerting them. Very classy.

[uncle W]

By the way, the latest available JMA SST anomaly, which is based on MAMJJ, is a surpringly warm +0.6. I would have expected a cooler number since it is centered on May. Then again, the JMA region is not the 3.4 region. Regardless, if anything, that gives me even more confidence that the ONI table is out of whack.

ftp://www.coaps.fsu.edu/pub/JMA_SST_Index/jmasst1868-today.filter-5

it's now up to +9...high for this time of year...this is the list of nino weak positive oni analogs since 1950...

season...JMA.. peak...

1997.........19.........33

1987.........12.........14

1972.........11.........20

1957.........11.........12

2009.........10.........14

2012...........9...........?

1991...........9.........14

1965...........9.........13

1951...........8.........12

1982...........8.........28

1992...........8...........8

1993...........8...........8

2002...........7.........11

1953...........6...........6

1963...........6...........8

2006...........5.........13

1976...........5.........10

1990...........4...........4

1958...........3...........3

2004...........2...........6

1979...........2...........5

1986...........1.........12

1994...........0...........9

2003...........0...........5

1977...........0...........3

1968...........0...........7

1952..........-1...........7

[GaWx]

it's now up to +9...high for this time of year...this is the list of nino weak positive oni analogs since 1950...

season...JMA.. peak...

1997.........19.........33

1987.........12.........14

1972.........11.........20

1957.........11.........12

2009.........10.........14

2012...........9...........?

1991...........9.........14

1965...........9.........13

Thanks, Unc. While the ONI table is out of whack in the too cool direction, the JMA seems out of whack in the too warm direction. So, the AMJJA # is +0.9. The avg. of the 3.4 weeklies for April-Aug. is only ~+0.25 and the 3.4 ONI (which I was already told by NOAA is out of whack too cool), was ~0.0. Then again, this is the JMA region, not 3.4. So, of course, they won't normally match and are often a bit off from each other. Regardless, the +0.9, +0.25, and 0.0 are further apart than is typical.

Regarding the JMA's +0.9 and your interesting table, this means that the 2012's AMJJA # of +0.9 has been matched or exceeded only by the listed seven Ninos that all peaked at strong ONIwise. Also, looking back at the eight oncoming Ninos of 1877-1930 that had +0.9+ for AMJJA, all eight went on to peak at strong in 3.4. So, in summary, there have been 15 times during 1877-2009 when the JMA's AMJJA reached or exceeded +0.9 during an oncoming Nino. All 15 ended up peaking as strong in 3.4!

By the way, I'm still going with a weak fall/winter ONI (corrected) peak for 2012-13 and am saying near zero chance for a high end moderate or strong peak.

[GaWx]

Per the following link, Nino 3.4 warmed back up even further today. So two days of warming. I'm expecting next Mon's weekly 3.4 SST anom. release to be warmer than the prior +0.3. We'll see.

http://www.esrl.noaa....anim.week.html

[uncle W]

Thanks, Unc. While the ONI table is out of whack in the too cool direction, the JMA seems out of whack in the too warm direction. So, the AMJJA # is +0.9. The avg. of the 3.4 weeklies for April-Aug. is only ~+0.25 and the 3.4 ONI (which I was already told by NOAA is out of whack too cool), was ~0.0. Then again, this is the JMA region, not 3.4. So, of course, they won't normally match and are often a bit off from each other. Regardless, the +0.9, +0.25, and 0.0 are further apart than is typical.

Regarding the JMA's +0.9 and your interesting table, this means that the 2012's AMJJA # of +0.9 has been matched or exceeded only by the listed seven Ninos that all peaked at strong ONIwise. Also, looking back at the eight oncoming Ninos of 1877-1930 that had +0.9+ for AMJJA, all eight went on to peak at strong in 3.4. So, in summary, there have been 15 times during 1877-2009 when the JMA's AMJJA reached or exceeded +0.9 during an oncoming Nino. All 15 ended up peaking as strong in 3.4!

By the way, I'm still going with a weak fall/winter ONI (corrected) peak for 2012-13 and am saying near zero chance for a high end moderate or strong peak.

I'm pretty new to following enso data but the MEI for JJ of 1.139 to 0.579 for JA seems out of wack...time will tell what number it peaks at for the oni and jma...The mei could have peaked last month if the data is correct...