ENSO Updates (2007 thru 2023)

[ozonepete]

To add more, your expertise in this area is quite apparent, great to see, and I admire it. again. When people post in a thread on one of our current Atlantic Basin TCs that we are in an El nino I'm going to invite you in to set them straight in a simple sentence. It has been very maddening to see people posting those incorrect statements in our TC threads, especially because there are a number of people there who don't have any scientific training (which is fine) but if they are turning to people they know and saying we have an El Nino going on that is just a shame. Hopefully they aren't saying that they got it from storm2k! I love the scientific integrity that storm2k has been nurturing and I hate to see it compromised. Especially when there are no significant atmospheric signatures of an El nino showing up over the Atlantic Basin yet, unless we should believe some of those posters over what the CPC says.

[Ntxw]

It's very much based on opinion ^. The Atlantic is further away so things don't happen instantly when there is El Nino or La Nina. The CPC declares ENSO in retrospect so we can only guess what the real conditions are. There isn't a magic line that once they declare it means that's when it instantly starts. Their definition of El Nino or La Nina is the appropriate anomalies for 5 consecutive trimonthlies. That means for 5 months before they declared it, the first month was when it began. Though they will tell us conditions have occurred when we get the first trimonthly. Example if it is declared in October, that means the ENSO event began July, and the next three months (July-August-September) featured anomalies equal to or greater than the needed SSTs.

Hope that helps clears some stuff . Right now they have not declared that trimonthly for June/July/August. LarryWx contacted the CPC as to why ONI was too low and they did indeed say it was. So we aren't not clear if it began in June. We won't know if it started in July until next month if it did. So on and so forth.

And you are right that there is no clear connection to El Nino-like features over in the Atlantic back in July and August. That doesn't mean the El Nino didn't exist, just that it was not influencing the Atlantic basin at the time.

[Kingarabian]

The PDO went from -0.87 in June to -1.93 in August. Ntxw, do you think this Nino can fight this PDO or it's days are numbered? I think the CFS model is still hinting on a somewhat moderate Nino.

[ozonepete]

It's very much based on opinion ^. The Atlantic is further away so things don't happen instantly when there is El Nino or La Nina. The CPC declares ENSO in retrospect so we can only guess what the real conditions are. There isn't a magic line that once they declare it means that's when it instantly starts. Their definition of El Nino or La Nina is the appropriate anomalies for 5 consecutive trimonthlies. That means for 5 months before they declared it, the first month was when it began. Though they will tell us conditions have occurred when we get the first trimonthly. Example if it is declared in October, that means the ENSO event began July, and the next three months (July-August-September) featured anomalies equal to or greater than the needed SSTs.

Hope that helps clears some stuff . Right now they have not declared that trimonthly for June/July/August. LarryWx contacted the CPC as to why ONI was too low and they did indeed say it was. So we aren't not clear if it began in June. We won't know if it started in July until next month if it did. So on and so forth.

And you are right that there is no clear connection to El Nino-like features over in the Atlantic back in July and August. That doesn't mean the El Nino didn't exist, just that it was not influencing the Atlantic basin at the time.

Wow you said a mouthful there. And in the interests of disclosure I already knew how the CPC determines an El Nino or La nina or ENSO neutral but I'm glad you posted it because many people here might not. So they have developed a looking-back method of analyzing it where any of us like me can say now in the present time that El Nino is going on and 1 to 5 months from now the data will prove I was right, unless it proves I was wrong. Then I can say I wasn't really wrong because I was right, or could have been right, at the time. My problem with all of this is that you can look at the trends now and see that we are not going to come up with a strong El Nino between now and 5 months from now unless the entire western PAC plunges into eternal darkness tomorrow. Just partially kidding.

And yes, my main point is that it is the atmospheric consequences for tropical cyclone development and strength that is why many of us over in the TC threads are interested in this in the first place. And it still bothers me that people have been posting over there since June that we are "in an El Nino" and that we won't have very many TCs while we are already up to Nadine. Look at the forecasting pool that cycloneye hosted before the season and note how many people posted that we would have very few TCs this year in the Atlantic because we "will be" or "are in El Nino." Beside the complications of TC strength versus numbers in the Atlantic in an El Nino, I would ask them "How's that workin' out?" The tropical atmosphere simply hasn't responded to the El Nino that many are saying is currently in progress. (And I don't mean you are saying that.) i.e. I don't see huge El Nino induced winter lows driving into southern California this winter, nor the Atlantic hurricane season shutting down tomorrow, unless there is some incredible upheaval coming that I can't imagine. And in a very weak El Nino, what are the big atmospheric consequences in the Atlantic Basin, or rather any consequences of significance there, that we should be looking for compared to say, an ENSO neutral? Isn't it like trying to decide what are the atmospheric consequences depending on whether an omega block will be centered at Omaha or Topeka? I guess I'm just trying to say that the relation of the currently small changes in ENSO to the Atlantic hurricane season may be very overrated. And there are too many people trying very hard to overrate it despite the pretty clear data and its apparent odds.

[NDG]

Sept 15th update, WOW!!!! Big change.
We can scratch the idea of a moderate El Nino, it will be barely a very weak El Nino at best if the new Seasonal Range Forecast is correct.



Edit: this is the Seasonal Range Forecast not the EUROSIP like I had initially typed.

[Ntxw]

Where did you get that NDG? I was looking at the Ecmwf site and couldn't find it, the updated Eurosip? I also noticed the image you posted was the channel 4 NCEP models which gets initiation data from CFS. Is there a multi-model chart which includes the euro/ukmet/canadian as well?

[NDG]

Where did you get that NDG? I was looking at the Ecmwf site and couldn't find it, the updated Eurosip? I also noticed the image you posted was the channel 4 NCEP models which gets initiation data from CFS. Is there a multi-model chart which includes the euro/ukmet/canadian as well?

Sorry, is not the EUROSIP, is the Seasonal Range forecast, I got confused.
I will correct it.

[Ntxw]

To be fair to it though, it isn't wrong to agree with it. Mid August Nino 3.4 did drop from .8c to .6, just that it has gone back up the last weeks in early Sept from the initiation point of NCEP.

[NDG]

I personally think that lately is has down close to .5

[Ntxw]

The PDO went from -0.87 in June to -1.93 in August. Ntxw, do you think this Nino can fight this PDO or it's days are numbered? I think the CFS model is still hinting on a somewhat moderate Nino.

PDO usually warms with the southern hemisphere summer unless there is a La Nina going on. Usually El Nino's have a tendency to flip the PDO a little bit warm by our winter months depending on how strong they are. So to answer your question I believe the PDO will lessen the next few months, but how much will depend on the Nino.

[ozonepete]

So what's the consensus here right now? Will we say 5 months from now that we were in a weak El Nino or ENSO neutral in September 2012? Or is it too weak of a signal to say?

[cycloneye]

Climate Prediction Center Weekly Update of 9/17/12

Nino 3.4 cools down to +0.5C from +0.8C that was last week and that is a very important downward occurance at this point.



http://www.cpc.ncep.noaa.gov/products/a ... ts-web.pdf

[Ntxw]

Wouldn't it be crazy if we had a period of La Nina anomalies? There actually is a pool of deeper sub-surface cool anomalies now at 160w. Like in late Sept of 09 this feature appeared but in that year the western warm pool then rose drastically and overwhelmed everything in October and we had a full fledged moderate nino. The PDO is colder this time go round so it will be interesting which will win out. We won't go to La Nina or cold neutral but it's still an interesting idea for the next few weeks before warming resumes.

[LarryWx]

So what's the consensus here right now? Will we say 5 months from now that we were in a weak El Nino or ENSO neutral in September 2012? Or is it too weak of a signal to say?

Very likely weak Nino. The weeklies suggest that 3.4 was +0.9 to +0.8 for first week or so and are now near +0.5.

[NDG]

So the Seasonal Range Forecast by the ECMWF released this past Saturday was correct after all of it forecasting Nino 3.4 to cool back down to near .5 by the middle of this month and could be correct of it forecasting to stay near .5 into next month.

[cycloneye]

Here is what Dr Jeff Masters has to say about El Nino Watch.

El Niño watch continues
Sea surface temperatures were at 0.5°C above average as of September 17 in the equatorial Pacific off the coast of South America, and have been near or above the 0.5°C above average--the threshold needed for a weak El Niño event--since the beginning of July. However, winds, pressures, and cloud cover over the region have not responded in the fashion typically associated with an El Niño, and NOAA's Climate Prediction Center (CPC) classified conditions as being neutral in their September 6 El Niño discussion. They continued their El Niño watch, and gave a 69% chance that an El Niño event will be in place by the end of September. El Niño conditions tend to decrease Atlantic hurricane activity, by increasing wind shear over the tropical Atlantic. Wind shear has been close to average over the tropical Atlantic since the beginning of hurricane season in June. However, the past few runs of the GFS model have predicted a significant rise in wind shear over the Caribbean and tropical Atlantic by early October, which may represent El Niño finally beginning to kick in and affect the atmospheric circulation over the Atlantic.

[weatherdude1108]

It can't kick in soon enough IMO.

[Cyclenall]

Here is what Dr Jeff Masters has to say about El Nino Watch.

El Niño watch continues
Sea surface temperatures were at 0.5°C above average as of September 17 in the equatorial Pacific off the coast of South America, and have been near or above the 0.5°C above average--the threshold needed for a weak El Niño event--since the beginning of July. However, winds, pressures, and cloud cover over the region have not responded in the fashion typically associated with an El Niño, and NOAA's Climate Prediction Center (CPC) classified conditions as being neutral in their September 6 El Niño discussion. They continued their El Niño watch, and gave a 69% chance that an El Niño event will be in place by the end of September. El Niño conditions tend to decrease Atlantic hurricane activity, by increasing wind shear over the tropical Atlantic. Wind shear has been close to average over the tropical Atlantic since the beginning of hurricane season in June. However, the past few runs of the GFS model have predicted a significant rise in wind shear over the Caribbean and tropical Atlantic by early October, which may represent El Niño finally beginning to kick in and affect the atmospheric circulation over the Atlantic.

This block of text has been repeated a lot this summer. Its been the same for a long while now. The bolded part: much more wind shear in the Caribbean? It has already been hostile to begin with this whole time!!

:uarrow:
It can't kick in soon enough IMO.

Yeah, we were all sweating bullets watching those weak CAT1 hurricanes thousands of miles away end up under-performing. I wouldn't mind it finishing the basin off either because I then wouldn't have to check up on it anymore every couple of days.

The PDO is colder this time go round so it will be interesting which will win out. We won't go to La Nina or cold neutral but it's still an interesting idea for the next few weeks before warming resumes.

I hope this happens, would throw everything off . The Nino 3.4 going down 0.3ºC in 1 week is a good start.

[Kingarabian]

Well the Caribbean has been hostile this season, yes. But the gulf was really conducive excluding the dry air. However, the GFS is now predicting extremely high shear in the gulf.

[ozonepete]

Just remember that shear forecasts, especially long-term ones, vary from pretty awful to very awful.