El nino developing??

[willjnewton]

is the current index as of Right now in august in the the Eastern pacific, Plus 0.5C or less???please explain okay, thankyou

[AussieMark]

the area we should be looking at is 5°N-5°S, 120°-170°W)

[AussieMark]

the Index in July was +0.1C

the Index doesn't usually come available till after the Month is over I thought

[WeatherWiseGuy]

Thanks AussieMark. That's exactly what I wanted to know!

[willjnewton]

I am assuming that for the month of august the index as of now is plus 0.4C am I correct???

[CycloneCarl]

There is a good bar graph of the average monthly Southern Oscillation Index (SOI) since 2003 here, updated monthly.

Whilst only part of the El Nino story, the SOI, which is an averaged index calculated from the daily atmospheric surface pressure difference between Tahiti and Darwin, is often a good indicator of where things are headed, with sea temperatures usually inversely following SOI trends some weeks later (i.e. temperatures rise after SOI falls).

As long as the SOI is within the range of about +10 to -10 conditions are considered neutral, and as you can see that the SOI has been weakly -ve for three months in a row, so indicating neutral conditions with an El Nino bias.

For up-to-date SOI values, there is a table here.

If you examine the table you will see that the last entry reads:

Code: Select all

Date            Tahiti    Darwin   Daily**    30 day    90 day
                                              Av.SOI    Av.SOI
20-Aug-2006    1011.52   1015.20    -32.10    -15.73    -11.48


You can see that the SOI is indicating the likely onset of an El Nino (SOI <-10), and if you look at the table you will see that the SOI has been below -10 since the 2nd of August (30 day av) and the 6th August (90 day av), and the -ve trend appears to be continuing.

If this trend does continue, we can expect to move into an 'official' El Nino within the next few months.

[willjnewton]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

[willjnewton]

I have been waiting for 15minutes and its getting late so can a pro met answer my question before I go to bed please, thanks

[AussieMark]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

from the latest BOM ENSO update was the following statement

Most of the ENSO prediction models surveyed at the end of July showed a continuation of neutral conditions, although on the warm side of normal. Two of the twelve models suggested the Pacific may warm to El Niño levels by the end of the southern spring. However, a sustained warming beginning in August or September would be unusual, given that ENSO events typically begin to evolve between March and June.

[DESTRUCTION5]

No EL Nino...Bed time

[cycloneye]

William,we will know more about how ENSO is doing on August 30th when the Australians release their latest outlook for ENSO.

[willjnewton]

okay thankyou

[kevin]

Cognitive functioning reasons (biological).

[Jim Hughes]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

from the latest BOM ENSO update was the following statement

Most of the ENSO prediction models surveyed at the end of July showed a continuation of neutral conditions, although on the warm side of normal. Two of the twelve models suggested the Pacific may warm to El Niño levels by the end of the southern spring. However, a sustained warming beginning in August or September would be unusual, given that ENSO events typically begin to evolve between March and June.

The latter part of this statement is the key to which most people do not understand. Even the professionals within the community. The exact forcing of the ENSO is not understood. Most people already know that I believe in the space weather forcing upon it.

A development at this time of the year would be unusual and the model's are built upon historical atmospheric interactions. So if unusual or unique circumstances were around then a warming could occur even though it went against the usual developmental norm.

September 1986 comes to mind and it also developed closed to solar minimum.

Now with that being said. The weekly SST temperatures are out for the four different ENSO regions and the region that everybody wants to officially go by, Region 3.4, is at +.5 .

All four different regions warmed and Regions 1+2 and 4 are at +.8 .

So the SST lovers, who disregard the importance of the SOI or MEI, have gotten their golden level of +.5. Now it needs to stay at this level, monthly wise, for three straight months.

An August +.5 reading might be hard to come by though without a bigger anomaly ahead because of the first two weekly indices. (+.4 and +.3) But someone might be able to look back at this week, lets say in early November, and say that an EL Nino was OFFICIALLY underway in mid August.

[bevgo]

are you all going to lock this threaD or NOT???

Might as well lock it. You'll make a new one anyway.

Was this necessary? Please be nice. It gets really old to see people being mean to another poster. Makes you afraid to ask a question.

[LarryWx]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

Now with that being said. The weekly SST temperatures are out for the four different ENSO regions and the region that everybody wants to officially go by, Region 3.4, is at +.5 .

All four different regions warmed and Regions 1+2 and 4 are at +.8 .

So the SST lovers, who disregard the importance of the SOI or MEI, have gotten their golden level of +.5. Now it needs to stay at this level, monthly wise, for three straight months.

An August +.5 reading might be hard to come by though without a bigger anomaly ahead because of the first two weekly indices. (+.4 and +.3) But someone might be able to look back at this week, lets say in early November, and say that an EL Nino was OFFICIALLY underway in mid August.

Good post Jim. I see no reason to not expect an official proclamation of El Nino soon (retroactively obviously).

[Mr. MidAtlantic]

are you all going to lock this threaD or NOT???

Might as well lock it. You'll make a new one anyway.

Was this necessary? Please be nice. It gets really old to see people being mean to another poster. Makes you afraid to ask a question.

He did'nt say anything wrong. He just told the truth, that's all. He did'nt call him any names or anything. Don't be so sensitive. I think Will has enough guardians on this board.

[benny]

The beauty is... no one knows if there is or isn't an El Nino forming. If there is one, it will happen. If there isn't one, it won't happen.

Remember.. El Nino is Spanish for.... The....Nino

LOL

[benny]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

Now with that being said. The weekly SST temperatures are out for the four different ENSO regions and the region that everybody wants to officially go by, Region 3.4, is at +.5 .

All four different regions warmed and Regions 1+2 and 4 are at +.8 .

So the SST lovers, who disregard the importance of the SOI or MEI, have gotten their golden level of +.5. Now it needs to stay at this level, monthly wise, for three straight months.

An August +.5 reading might be hard to come by though without a bigger anomaly ahead because of the first two weekly indices. (+.4 and +.3) But someone might be able to look back at this week, lets say in early November, and say that an EL Nino was OFFICIALLY underway in mid August.

Good post Jim. I see no reason to not expect an official proclamation of El Nino soon (retroactively obviously).

Well, the CPC definition of El Nino is 5 consecutive seasons of 0.5C or greater in Nino 3.4. I believe the 04-05 event had 4 seasons (4- 3 month periods) so it was just short. Whatever the case.. this definition is rather lacking for effects on Atlantic Hurricane Seasons.

What I'm looking at is the persistance of upper-level anticyclone near the dateline in the northern and southern hemisphere. This has continued for a while now along with westerly wind anomalies for about the past two months... all signs of El Nino. This is also the type of event that would shut the Atlantic hurricane season down by displacing the Walker Circulation... and causing more subsidence than average in the Atlantic, along with stronger ridges with less cyclonic vorticity... and usually more shear, especially in the Caribbean. We aren't at the point yet (but soon) that the season is doomed from being active.. but the longer the western pacific keeps acting like El Nino ... the worse off we will be (if you like Atlantic hurricanes). I'm curious the role that Ioke will have.. as it is now forecast to persist beyond the dateline as a hurricane... and continue the anomalous anticyclone in the area. In any event... it looks like with an active MJO-like pulse coming through the Atlantic.. we'll have some storms.. but in about 2 weeks... will the Atlantic be quiet (except for high-latitude systems?) ???? big questions. The Atlantic is quite warm so maybe that will help offset some effects.. but......

I would expect Gray and TSR to lower their numbers significantly on Sept 1.

[Jim Hughes]

I think that we are in a very weal el nino Now does anyone agree?? and if we are in a weak el nino how would that affect this 2006 storm or hurricane season???

Now with that being said. The weekly SST temperatures are out for the four different ENSO regions and the region that everybody wants to officially go by, Region 3.4, is at +.5 .

All four different regions warmed and Regions 1+2 and 4 are at +.8 .

So the SST lovers, who disregard the importance of the SOI or MEI, have gotten their golden level of +.5. Now it needs to stay at this level, monthly wise, for three straight months.

An August +.5 reading might be hard to come by though without a bigger anomaly ahead because of the first two weekly indices. (+.4 and +.3) But someone might be able to look back at this week, lets say in early November, and say that an EL Nino was OFFICIALLY underway in mid August.

Good post Jim. I see no reason to not expect an official proclamation of El Nino soon (retroactively obviously).

Well, the CPC definition of El Nino is 5 consecutive seasons of 0.5C or greater in Nino 3.4. I believe the 04-05 event had 4 seasons (4- 3 month periods) so it was just short. Whatever the case.. this definition is rather lacking for effects on Atlantic Hurricane Seasons.

What I'm looking at is the persistance of upper-level anticyclone near the dateline in the northern and southern hemisphere. This has continued for a while now along with westerly wind anomalies for about the past two months... all signs of El Nino. This is also the type of event that would shut the Atlantic hurricane season down by displacing the Walker Circulation... and causing more subsidence than average in the Atlantic, along with stronger ridges with less cyclonic vorticity... and usually more shear, especially in the Caribbean. We aren't at the point yet (but soon) that the season is doomed from being active.. but the longer the western pacific keeps acting like El Nino ... the worse off we will be (if you like Atlantic hurricanes). I'm curious the role that Ioke will have.. as it is now forecast to persist beyond the dateline as a hurricane... and continue the anomalous anticyclone in the area. In any event... it looks like with an active MJO-like pulse coming through the Atlantic.. we'll have some storms.. but in about 2 weeks... will the Atlantic be quiet (except for high-latitude systems?) ???? big questions. The Atlantic is quite warm so maybe that will help offset some effects.. but......

I would expect Gray and TSR to lower their numbers significantly on Sept 1.

It only has to be > .5 for three consectutives months Benny not five. As for 2004-05. It met the criteria of their definition. So you tell me why they tend to downplay it's existence .

7/04 + .61
8/04 + .83
9/04 + .83
10/04 + .79
11/04 +.79
12/04 +.84
01/05 + .59

It was weaker than 2002 but one has to wonder if the reason centers around their lack of forecasting it. Or how it hardly did anything to the 04 tropical season. The tropics quieted down after the September 90 day SOI average became extremely high not while the SST's got above .5 The latter first happened in July 04 as the above numbers show.

So the guideline that everyone around here likes to go by was useless back then and it's been useless this season as well. The extremeness in the 90 SOI average ( > 10.0-11.0) is a much better indicator of how the atmosphere is behaving when it comes to forecasting tropical activity.

This is what I have been trying to get across within this forum. What you think is correct is not always true.

As for the probable storm total lowering ahead. I would tend to agree. We are currently running at 33% of last years pace. That would put us right around average if this were to continue. (10/5/2)

On another note. The winter of 04-05 had plenty of EL Nino characteristics. Just ask the people in Southern/Central California. Storm after storm.