El nino developing??

[benny]

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.

No, actually here is their definition found at:
http://www.cpc.noaa.gov/products/analys ... ears.shtml

"Warm (red) and cold (blue) episodes based on a threshold of +/- 0.5oC for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v2 SST anomalies in the Niño 3.4 region (5oN-5oS, 120o-170oW)], based on the 1971-2000 base period. For historical purposes cold and warm episodes (blue and red colored numbers) are defined when the threshold is met for a minimum of 5 consecutive over-lapping seasons."

Just because it is above 0.5 for 3 months doesn't qualify it as a Nino for historical purposes.

The SOI might be more appropriate but over the long haul, the Nino 3.4 SSTs have worked the same as the SOI. The SOI is just two places on the globe and really doens't capture all the variability across the globe.

Look NOAA lowered its forecast in Aug 04 b/c of all the warm water if I remembered correctly and got burned. Past performance isn't necesarily indicative of the future of course... so maybe this year the SOI will be a better indicator. I don't have a whole lot else to add other than we have a long ways to go in understanding when weak/moderate el Ninos like 1969 and 2004 do zero to the Atlantic season when seemingly similar episodes like 2006 or 1968 "may" crush the season.

[Jim Hughes]

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.

No, actually here is their definition found at:
http://www.cpc.noaa.gov/products/analys ... ears.shtml

"Warm (red) and cold (blue) episodes based on a threshold of +/- 0.5oC for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v2 SST anomalies in the Niño 3.4 region (5oN-5oS, 120o-170oW)], based on the 1971-2000 base period. For historical purposes cold and warm episodes (blue and red colored numbers) are defined when the threshold is met for a minimum of 5 consecutive over-lapping seasons."

Just because it is above 0.5 for 3 months doesn't qualify it as a Nino for historical purposes.

The SOI might be more appropriate but over the long haul, the Nino 3.4 SSTs have worked the same as the SOI. The SOI is just two places on the globe and really doens't capture all the variability across the globe.

Look NOAA lowered its forecast in Aug 04 b/c of all the warm water if I remembered correctly and got burned. Past performance isn't necesarily indicative of the future of course... so maybe this year the SOI will be a better indicator. I don't have a whole lot else to add other than we have a long ways to go in understanding when weak/moderate el Ninos like 1969 and 2004 do zero to the Atlantic season when seemingly similar episodes like 2006 or 1968 "may" crush the season.

This NOAA news release article of a new and agreed upon worldwide definition mentions nothing about a running mean. I have never heard any well versed MET's talk about a running mean either. The three month mean just keeps someone from claiming an El Nino would be present with numbers like at +.5, +.4 , +.5 . But three + .5 in a row constitues a warming phase.

Maybe GaWx might chime in here. He is well versed on the ENSO.

http://www.noaanews.noaa.gov/stories2005/s2428.htm

[Jim Hughes]

Benny,

I just took a look at the link you supplied. It talks about a running mean. I just love NOAA's consistency here.

[wxmann_91]

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

I heard it was the Madden Jullian Oscillation that caused that. Anyhow El Nino probably did have something to do with it.

BTW, GaWx's name here is LarryWx, Jim.

[LarryWx]

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.

No, actually here is their definition found at:
http://www.cpc.noaa.gov/products/analys ... ears.shtml

"Warm (red) and cold (blue) episodes based on a threshold of +/- 0.5oC for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v2 SST anomalies in the Niño 3.4 region (5oN-5oS, 120o-170oW)], based on the 1971-2000 base period. For historical purposes cold and warm episodes (blue and red colored numbers) are defined when the threshold is met for a minimum of 5 consecutive over-lapping seasons."

Just because it is above 0.5 for 3 months doesn't qualify it as a Nino for historical purposes.

The SOI might be more appropriate but over the long haul, the Nino 3.4 SSTs have worked the same as the SOI. The SOI is just two places on the globe and really doens't capture all the variability across the globe.

Look NOAA lowered its forecast in Aug 04 b/c of all the warm water if I remembered correctly and got burned. Past performance isn't necesarily indicative of the future of course... so maybe this year the SOI will be a better indicator. I don't have a whole lot else to add other than we have a long ways to go in understanding when weak/moderate el Ninos like 1969 and 2004 do zero to the Atlantic season when seemingly similar episodes like 2006 or 1968 "may" crush the season.

This NOAA news release article of a new and agreed upon worldwide definition mentions nothing about a running mean. I have never heard any well versed MET's talk about a running mean either. The three month mean just keeps someone from claiming an El Nino would be present with numbers like at +.5, +.4 , +.5 . But three + .5 in a row constitues a warming phase.

Maybe GaWx might chime in here. He is well versed on the ENSO.

http://www.noaanews.noaa.gov/stories2005/s2428.htm

Jim/Benny,

1) El Nino def.:
NOAA's official El Nino definition requires five trimonthly NINO 3.4 +0.5 C anom.'s in a row per this link, which I abide by in any posts addressing NOAA's def.:
http://www.cpc.ncep.noaa.gov/products/a ... ears.shtml

2) As Jim suggests, I think that the SOI (specifically Aug) may, indeed, be a more reliable leading indicator than actual SST's. Aug. of 2006 will definitely end up lower than -10. I'm currently thinking it will end up near the -14 to -15 range. Whereas the Aug SOI during or preceding an El Nino is often <-10, it isn't always, especially prior to some weak El Nino's. 1969's was only down to -4.0 and 2004's was only down to -6.7. So, maybe that's the critical connection to try to explain why those seasons were not quiet unlike the average El Nino season?? In contrast, the following 20 August's had an SOI <-10:

2002, 1997, 1994, 1993, 1987, 1982, 1977, 1976, 1965, 1953, 1941, 1940, 1934, 1925, 1923, 1014, 1911, 1896, 1882, and 1881

What did these 20 hurricane seasons all have in common? There were no more than six hurricanes officially in any one of these 20 seasons in contrast to the 12 of 1969 and the 9 of 2004! Twenty is no small potatoes when it comes to stat. significance. Is 2006 going to break that streak? Well, so far at least, it isn't headed in that direction. My June prediction at the Eastern wx BB was for only four H fwiw.

[wxmann_91]

1) El Nino def.:
NOAA's official El Nino definition requires five trimonthly NINO 3.4 +0.5 C anom.'s in a row per this link, which I abide by in any posts addressing NOAA's def.:
http://www.cpc.ncep.noaa.gov/products/a ... ears.shtml

2) As Jim suggests, I think that the SOI (specifically Aug) may, indeed, be a more reliable leading indicator than actual SST's. Aug. of 2006 will definitely end up lower than -10. Whereas the Aug SOI during or preceding an El Nino is often <-10, it isn't always, especially prior to some weak El Nino's. 1969's was only down to -4.0 and 2004's was only down to -6.7. So, maybe that's the critical connection to try to explain why those seasons were not quiet unlike the average El Nino season?? In contrast, the following 20 August's had an SOI <-10:

2002, 1997, 1994, 1993, 1987, 1982, 1977, 1976, 1965, 1953, 1941, 1940, 1934, 1925, 1923, 1014, 1911, 1896, 1882, and 1881

What did these 20 hurricane season all have in common? There were no more than six hurricanes officially in any one of these 20 seasons in contrast to the 12 of 1969 and the 9 of 2004! Is 2006 going to break that streak? Well, so far at least, it isn't headed in that direction. My June prediction at the Eastern wx BB was for only four H fwiw.

Larry,

Although this year may finish with few more than 6 hurricanes, I believe your prediction is too low. 1997 and 2002 had strong Nino's, something which will not occur this year. The rest of the years were either in an -AMO cycle, or were in the pre-satellite era.

If we filter the search and just focus on August -SOI's <-10, weak/mod Nino's, and +AMO, we would not have many analog years in the satellite era, if any.

[Jim Hughes]

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.

No, actually here is their definition found at:
http://www.cpc.noaa.gov/products/analys ... ears.shtml

"Warm (red) and cold (blue) episodes based on a threshold of +/- 0.5oC for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v2 SST anomalies in the Niño 3.4 region (5oN-5oS, 120o-170oW)], based on the 1971-2000 base period. For historical purposes cold and warm episodes (blue and red colored numbers) are defined when the threshold is met for a minimum of 5 consecutive over-lapping seasons."

Just because it is above 0.5 for 3 months doesn't qualify it as a Nino for historical purposes.

The SOI might be more appropriate but over the long haul, the Nino 3.4 SSTs have worked the same as the SOI. The SOI is just two places on the globe and really doens't capture all the variability across the globe.

Look NOAA lowered its forecast in Aug 04 b/c of all the warm water if I remembered correctly and got burned. Past performance isn't necesarily indicative of the future of course... so maybe this year the SOI will be a better indicator. I don't have a whole lot else to add other than we have a long ways to go in understanding when weak/moderate el Ninos like 1969 and 2004 do zero to the Atlantic season when seemingly similar episodes like 2006 or 1968 "may" crush the season.

This NOAA news release article of a new and agreed upon worldwide definition mentions nothing about a running mean. I have never heard any well versed MET's talk about a running mean either. The three month mean just keeps someone from claiming an El Nino would be present with numbers like at +.5, +.4 , +.5 . But three + .5 in a row constitues a warming phase.

Maybe GaWx might chime in here. He is well versed on the ENSO.

http://www.noaanews.noaa.gov/stories2005/s2428.htm

Jim/Benny,

1) El Nino def.:
NOAA's official El Nino definition requires five trimonthly NINO 3.4 +0.5 C anom.'s in a row per this link, which I abide by in any posts addressing NOAA's def.:
http://www.cpc.ncep.noaa.gov/products/a ... ears.shtml

2) As Jim suggests, I think that the SOI (specifically Aug) may, indeed, be a more reliable leading indicator than actual SST's. Aug. of 2006 will definitely end up lower than -10. I'm currently thinking it will end up near the -14 to -15 range. Whereas the Aug SOI during or preceding an El Nino is often <-10, it isn't always, especially prior to some weak El Nino's. 1969's was only down to -4.0 and 2004's was only down to -6.7. So, maybe that's the critical connection to try to explain why those seasons were not quiet unlike the average El Nino season?? In contrast, the following 20 August's had an SOI <-10:

2002, 1997, 1994, 1993, 1987, 1982, 1977, 1976, 1965, 1953, 1941, 1940, 1934, 1925, 1923, 1014, 1911, 1896, 1882, and 1881

What did these 20 hurricane seasons all have in common? There were no more than six hurricanes officially in any one of these 20 seasons in contrast to the 12 of 1969 and the 9 of 2004! Twenty is no small potatoes when it comes to stat. significance. Is 2006 going to break that streak? Well, so far at least, it isn't headed in that direction. My June prediction at the Eastern wx BB was for only four H fwiw.

Well the five months add up Larry if it is a running mean. You need the two extra's to come up with three different months. The link supports this also.

And to follow up on some of your comments. (BTW Larry has been writing up some excellent discussions somewhere else involving many different things with the SOI , El Nino , and hurricane activity. Some of you should try and read them. )

The 90 day average SOI climbed above -10.0 Larry on 9/4/04. The season quieted down within 2-4 weeks. During the summer of 2002 it fell down to as low as - 5.80 on June 17th before heading back up. The real consistent > - 10.0 90 day SOI average did not show up until 9/11/02. The season came to an end within 2-4 weeks.

I know you look at Long Paddock also and you can easily see what years (Summer/Fall ) had 90 day averages > 10.0 when looking over the monthly data. The individual years that I looked at months ago showed a strong correlations between decreased hurricane activity and this strong negative SOI level.

The 30 day SOI average can be quite volatile but the 90 day average is not. An extreme like this makes a statement when it is at this current level and it is a strong indicator of the state of the atmosphere, regardless of whether it is a positive or negative SOI. Even without the proper SST's anomalies present.

So this persistent 90 day SOI average, that has been over the -10.0 level since August 6th, has some meaning here in my opinion. And I firmly believe that "IF" it stays above this level that this years hurricane season might even be quieter than 2002. At least in the total number of storms. We saw twelve that season.

[Jim Cantore]

I find it hard to believe that we had an El Nino in 2004, considering what happened. But it was there.

As for this year, I think a Mild to Moderate El Nino will show, considering we are already seeing signs.

[HurricaneBill]

I find it hard to believe that we had an El Nino in 2004, considering what happened. But it was there.

Just ask Japan. There was definitely an El Nino.

[Derek Ortt]

there was an el nino in 2004

after Jeanne the season was basically shut down, and that was in late September

[Jim Hughes]

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

I heard it was the Madden Jullian Oscillation that caused that. Anyhow El Nino probably did have something to do with it.

BTW, GaWx's name here is LarryWx, Jim.

Yes I heard this possibility to. But they are interconnected. Certain signs pointed away from an ENSO connection to the storminess and I believe it was also related to some things in the NP but I could be mistaken here. Someone can correct me if I am wrong.

This was also just a weak event. So all things might not have fit the usual wintertime El Nino analog. But anyone using it, which I did, got a boost from thinking it was an ENSO winter.

This is where both skill and conjecture come into play when you are trying to long term forecast an upcoming season. Whether it be a wintertime pattern or the tropics. We have seen this over at eastern already in regards to this upcoming winter and it's just August.

BTW thanks for the heads up about Larry.

[Jim Hughes]

there was an el nino in 2004

after Jeanne the season was basically shut down, and that was in late September

Yes it did. Only four systems formed after September 19th and Lisa, which formed on the 19th, was the only one to make it to hurricane status. And she was only a CAT 1. Jeanne and Karl formed on the 13th and 16th and they became Majors.

But once again. I go back to my earlier comments about the 90 day SOI average . On August 9th it was just -4.2. and then it climbed considerably. So the longer wave within the SOI index is much more important here.

[Steve]

>>The real consistent > - 10.0 90 day SOI average did not show up until 9/11/02. The season came to an end within 2-4 weeks.

While I only read the last couple of posts on the thread, how is this possible to even play as the result of El Nino? For grins and giggles, 4 weeks would be 10/11/02. Two weeks later (part of your time frame), I personally caught the edge of Tropical Storm Isidore's eyewall - that was on 9/26/06. Lili then hit on the 3rd of October and we got some action here. Tropical Depression #14 hit the Greater Antilies around October 16th.

But tying the end of the storm season with those SOI readings is dubious IMHO. How many seasons are we essentially done by mid October anyway? Some years have an October Gulf or Caribbean system and sometimes we see November storms, but they are the exception rather than the rule. So attributing the end of the Atlantic Season to the SOI values less than -10 (or is that greater than, I'm terrible with negative integers) doesn't necessarily add up. It may just be a function of the end of the season. FWIW, there was a named Pacific Storm that crossed Mexico as tropical energy and moved NEward across the Gulf and brought me rain even after the season was over. It was formerly tropical and brought my PERSONALLY OBSERVED RAINFALL FROM TROPICAL SYSTEMS that year to 7. (Bertha, Eduoard {in Fay}, Fay, Isidore, Lili, ex EPAC).

Steve

[Steve]

Oops - Forgot Hanna in that count!

Steve

[LarryWx]

1) El Nino def.:
2) As Jim suggests, I think that the SOI (specifically Aug) may, indeed, be a more reliable leading indicator than actual SST's. Aug. of 2006 will definitely end up lower than -10. Whereas the Aug SOI during or preceding an El Nino is often <-10, it isn't always, especially prior to some weak El Nino's. 1969's was only down to -4.0 and 2004's was only down to -6.7. So, maybe that's the critical connection to try to explain why those seasons were not quiet unlike the average El Nino season?? In contrast, the following 20 August's had an SOI <-10:

2002, 1997, 1994, 1993, 1987, 1982, 1977, 1976, 1965, 1953, 1941, 1940, 1934, 1925, 1923, 1014, 1911, 1896, 1882, and 1881

What did these 20 hurricane season all have in common? There were no more than six hurricanes officially in any one of these 20 seasons in contrast to the 12 of 1969 and the 9 of 2004! Is 2006 going to break that streak? Well, so far at least, it isn't headed in that direction. My June prediction at the Eastern wx BB was for only four H fwiw.

Larry,

Although this year may finish with few more than 6 hurricanes, I believe your prediction is too low. 1997 and 2002 had strong Nino's, something which will not occur this year. The rest of the years were either in an -AMO cycle, or were in the pre-satellite era.

If we filter the search and just focus on August -SOI's <-10, weak/mod Nino's, and +AMO, we would not have many analog years in the satellite era, if any.

wxmann_91,
You bring up good points, but I'm already aware of them and still feel good about my 4 H prediction. Here's why:

1) Yrs. w/Aug SOI<-10 since 1960:

- +AMO: three yrs. w/avg. SOI -14.1 and these # H: 4, 3, 4 for avg. of 3.7 H's/yr.

- -AMO: six yrs. w/ avg. SOI -14.4 and these # H: 3, 4, 3, 2, 5, 6 for avg. of 3.8 H's/yr.

Note the lack of increase in avg. H's for years since 1960 w/Aug SOI<-10 when going from -AMO to +AMO. Also note that the two SOI averages are essentially equal.

***The point is there is no obvious indication that the +AMO had a large positive impact on # H's for these SATELLITE ERA yrs..****

Keeping this in mind, we've had nine yrs. w/Aug SOI<-10 since 1960. Out of these nine, SEVEN (78%) have had four or fewer H's!! The two that didn't had two of the three least negative SOI's (both -11.1). I'm expecting the 8/06 SOI to end up a good bit more negative, (-14 to -15 range).

With stats such as all of these, why shouldn't I have predicted only 4 H's for 2006? None show good support for going any higher whatsoever!

I feel that I could easily stop here, but will cite some more stats in case you're still not convinced.

2) Based on eyeballing the top chart at the following link, there have been 38 +AMO regime years during the pre-satellite era since 1876 (i.e., 1876-1959) for which the Aug SOI was >-10:

http://en.wikipedia.org/wiki/Image:Amo_fig.JPG

-For these 38 pre-sat. +AMO yrs. w/Aug SOI>-10, the avg. H's was 5.7

- For the 9 +AMO yrs. since 1876 for which Aug SOI<-10, the avg. H's was only 4.4 (23% fewer than 5.7). (Actually, the chart suggests to me that 1993 and 1994 were already within the current +AMO regime. However, for this analysis, I'll consider it to have started in 1995.)

3) There have been 14 +AMO regime years since 1960 for which the Aug SOI was >-10:

- For these 14 +AMO yrs. w/Aug SOI>-10, the avg. H's was 8.1.

- For the 3 +AMO regime years since 1960 for which Aug SOI<-10, the avg. H's was only 3.7 (54% fewer than 8.1).

4) +AMO yrs. with 7+ H's:

- For the 38 +AMO regime yrs. during pre-satellite era since 1876 when Aug SOI>-10, there were still 14 yrs. (37%) with 7+ H's.

- For the 9 +AMO regime years since 1876 for which Aug SOI<-10, NONE had 7+ H's and only three had 5+ H's. Since 1960, NONE of these had more than four H's.


5) I consider 2002 to have been a moderate rather than strong El Nino since the trimonthly NINO 3.4 SST peak never exceeded +1.5 C.

6) The strength of El Nino (i.e. SST's) is really irrelevant to this analysis of mine since the whole point of it was to point out that the Aug SOI appears to be a more reliable indicator for the hurricane season.
-Larry

[Jim Hughes]

>>The real consistent > - 10.0 90 day SOI average did not show up until 9/11/02. The season came to an end within 2-4 weeks.

While I only read the last couple of posts on the thread, how is this possible to even play as the result of El Nino? For grins and giggles, 4 weeks would be 10/11/02. Two weeks later (part of your time frame), I personally caught the edge of Tropical Storm Isidore's eyewall - that was on 9/26/06. Lili then hit on the 3rd of October and we got some action here. Tropical Depression #14 hit the Greater Antilies around October 16th.

But tying the end of the storm season with those SOI readings is dubious IMHO. How many seasons are we essentially done by mid October anyway? Some years have an October Gulf or Caribbean system and sometimes we see November storms, but they are the exception rather than the rule. So attributing the end of the Atlantic Season to the SOI values less than -10 (or is that greater than, I'm terrible with negative integers) doesn't necessarily add up. It may just be a function of the end of the season. FWIW, there was a named Pacific Storm that crossed Mexico as tropical energy and moved NEward across the Gulf and brought me rain even after the season was over. It was formerly tropical and brought my PERSONALLY OBSERVED RAINFALL FROM TROPICAL SYSTEMS that year to 7. (Bertha, Eduoard {in Fay}, Fay, Isidore, Lili, ex EPAC).

Steve

If you read my post I am basically talking about a 3-4 week lag time. So your obaervations, while correct , are meaningless when it comes to the relationship.

The season quieted down on both ocassions considerably. We have been in a heightened level with the + AMO since 1995 , which should come into play here when considering how the overall seasons behave.

These are the only two seasons, along with 1997 , in which the 90 day average reached > -10.0 . You look at all the other seasons since 1995 and you tell me there is no difference here?

Please do not try and tell me that it was supposed to quiet down like we are back in the 90's. We had eight tropical sytems form after October 15th last year and two ended up being majors. And two systems were present in December.

[Jim Hughes]

1) El Nino def.:
2) As Jim suggests, I think that the SOI (specifically Aug) may, indeed, be a more reliable leading indicator than actual SST's. Aug. of 2006 will definitely end up lower than -10. Whereas the Aug SOI during or preceding an El Nino is often <-10, it isn't always, especially prior to some weak El Nino's. 1969's was only down to -4.0 and 2004's was only down to -6.7. So, maybe that's the critical connection to try to explain why those seasons were not quiet unlike the average El Nino season?? In contrast, the following 20 August's had an SOI <-10:

2002, 1997, 1994, 1993, 1987, 1982, 1977, 1976, 1965, 1953, 1941, 1940, 1934, 1925, 1923, 1014, 1911, 1896, 1882, and 1881

What did these 20 hurricane season all have in common? There were no more than six hurricanes officially in any one of these 20 seasons in contrast to the 12 of 1969 and the 9 of 2004! Is 2006 going to break that streak? Well, so far at least, it isn't headed in that direction. My June prediction at the Eastern wx BB was for only four H fwiw.

Larry,

Although this year may finish with few more than 6 hurricanes, I believe your prediction is too low. 1997 and 2002 had strong Nino's, something which will not occur this year. The rest of the years were either in an -AMO cycle, or were in the pre-satellite era.

If we filter the search and just focus on August -SOI's <-10, weak/mod Nino's, and +AMO, we would not have many analog years in the satellite era, if any.

wxmann_91,
You bring up good points, but I'm already aware of them and still feel good about my 4 H prediction. Here's why:

1) Yrs. w/Aug SOI<-10 since 1960:

- +AMO: three yrs. w/avg. SOI -14.1 and these # H: 4, 3, 4 for avg. of 3.7 H's/yr.

- -AMO: six yrs. w/ avg. SOI -14.4 and these # H: 3, 4, 3, 2, 5, 6 for avg. of 3.8 H's/yr.

Note the lack of increase in avg. H's for years since 1960 w/Aug SOI<-10 when going from -AMO to +AMO. Also note that the two SOI averages are essentially equal.

***The point is there is no obvious indication that the +AMO had a large positive impact on # H's for these SATELLITE ERA yrs..****

Keeping this in mind, we've had nine yrs. w/Aug SOI<-10 since 1960. Out of these nine, SEVEN (78%) have had four or fewer H's!! The two that didn't had two of the three least negative SOI's (both -11.1). I'm expecting the 8/06 SOI to end up a good bit more negative, (-14 to -15 range).

With stats such as all of these, why shouldn't I have predicted only 4 H's for 2006? None show good support for going any higher whatsoever!

I feel that I could easily stop here, but will cite some more stats in case you're still not convinced.

2) Based on eyeballing the top chart at the following link, there have been 38 +AMO regime years during the pre-satellite era since 1876 (i.e., 1876-1959) for which the Aug SOI was >-10:

http://en.wikipedia.org/wiki/Image:Amo_fig.JPG

-For these 38 pre-sat. +AMO yrs. w/Aug SOI>-10, the avg. H's was 5.7

- For the 9 +AMO yrs. since 1876 for which Aug SOI<-10, the avg. H's was only 4.4 (23% fewer than 5.7). (Actually, the chart suggests to me that 1993 and 1994 were already within the current +AMO regime. However, for this analysis, I'll consider it to have started in 1995.)

3) There have been 14 +AMO regime years since 1960 for which the Aug SOI was >-10:

- For these 14 +AMO yrs. w/Aug SOI>-10, the avg. H's was 8.1.

- For the 3 +AMO regime years since 1960 for which Aug SOI<-10, the avg. H's was only 3.7 (54% fewer than 5.7).

4) +AMO yrs. with 7+ H's:

- For the 38 +AMO regime yrs. during pre-satellite era since 1876 when Aug SOI>-10, there were still 14 yrs. (37%) with 7+ H's.

- For the 9 +AMO regime years since 1876 for which Aug SOI<-10, NONE had 7+ H's and only three had 5+ H's. Since 1960, NONE of these had more than four H's.


5) I consider 2002 to have been a moderate rather than strong El Nino since the trimonthly NINO 3.4 SST peak never exceeded +1.5 C.

6) The strength of El Nino (i.e. SST's) is really irrelevant to this analysis of mine since the whole point of it was to point out that the Aug SOI appears to be a more reliable indicator for the hurricane season.
-Larry

Nice stats Larry.

[benny]

The North Atlantic is quite warm this year... that should not be discounted in the Atlantic seasonal forecast. 2002 was closer to average. the formation of Lili and Isidore that year were a little surprising given the stronger ENSO forcing.. but that just goes to show that when the North Atlantic is warm, it tends to produce more hurricanes that you think. Historically speaking.. I believe Gray has used water temps more than the SOI as a predictor... the SOI can have too much month to month variability to be useful. The list of years with the low SOIs is indeed troubling for the seasonal forecasts... which I think look a little high given the past.

[LarryWx]

Nice stats Larry.

Thanks Jim. Please note that I just corrected one typo in that post:

" - For the 3 +AMO regime years since 1960 for which Aug SOI<-10, the avg. H's was only 3.7 (54% fewer than 5.7)."

This was corrected to the following:

"- For the 3 +AMO regime years since 1960 for which Aug SOI<-10, the avg. H's was only 3.7 (54% fewer than 8.1)."

[Jim Hughes]

The North Atlantic is quite warm this year... that should not be discounted in the Atlantic seasonal forecast. 2002 was closer to average. the formation of Lili and Isidore that year were a little surprising given the stronger ENSO forcing.. but that just goes to show that when the North Atlantic is warm, it tends to produce more hurricanes that you think. Historically speaking.. I believe Gray has used water temps more than the SOI as a predictor... the SOI can have too much month to month variability to be useful. The list of years with the low SOIs is indeed troubling for the seasonal forecasts... which I think look a little high given the past.

I agree about the favorable ATL conditions and of course they need to be considered. I even wrote something up a few weeks back about the battle between the developing El Nino and the favorable AMO conditions.

Some other people even brought up the fact that the AMO numbers had been revised recently and I believe they said that the 06 numbers were higher than even 2005.

As far as Dr Gray and the SOI. I never heard about Gray using the moving 90 day SOI average. The 30 day is very volatile Benny but the 90 day is much more consistent. Especially in regards to it reaching extreme thresholds. This does not happen to often even while you can see the 30 day average reach the -/+ 25-30 range.

The 90 day average fell below -10.0 on June 18th 1998 after the strong El Nino of 97-98 weakened. The 90 day average only reached the -10 threshold a little less than 3 % of the time during the next 2975 days. (Not including the recent run that started in early August)

Now the current string of days, in which the 90 day average is > -10, is at 19 days and it still has enough daily negative days in the in the bank to get a few more qualified days even with a minor positive SOI stretch. (It will fall below this value by next week if the daily average stays neutral - positve.)

The longest run in 2002 was 25 days. So it is very possible that we might exceed that run by the end of next week.