ENSO Updates (2007 thru 2023)

[SFLcane]

The Niño weakening coupled w/ extremely warm CPAC & cool SEPAC will definitely promote a +PMM pattern. Since we've passed the summer solstice this means it will actually be unfavorable for Niño growth (but will switch to favorable if it persists into fall), but unfortunately will allow the ITCZ to move northward and make the CPAC active

https://pbs.twimg.com/media/D96Uu6kXUAEkGig?format=png

Epac is really cooling...

[Kingarabian]

[url]https://twitter.com/TylerJStanfield/status/1143597932802912256[url]

But we still need to see some sort of cooperation from the atmosphere to see El Nino wash out by the fall. Because we saw the same thing happen around mid May before a WWB came on. There are arguments to be made that this upwelling Kelvin wave is stronger, however it still has quite a bit of warmth to overcome.


So we can't see any WWB's and there must be EWB's throughout July.

[NotSparta]

[url]https://twitter.com/TylerJStanfield/status/1143597932802912256[url]

But we still need to see some sort of cooperation from the atmosphere to see El Nino wash out by the fall. Because we saw the same thing happen around mid May before a WWB came on. There are arguments to be made that this upwelling Kelvin wave is stronger, however it still has quite a bit of warmth to overcome.
https://i.imgur.com/Zyki57w.png

So we can't see any WWB's and there must be EWB's throughout July.

Well, things are definitely stacked for July not to have a WWB (outside brief 5m/s anomalies), the weak MJO will mean insufficient forcing for WWB activity, and the PMM phase will soon favor EWBs, as well as make WWBs more difficult to come by, by moving them northward away from the equator

[Kingarabian]

[url]https://twitter.com/TylerJStanfield/status/1143597932802912256[url]

But we still need to see some sort of cooperation from the atmosphere to see El Nino wash out by the fall. Because we saw the same thing happen around mid May before a WWB came on. There are arguments to be made that this upwelling Kelvin wave is stronger, however it still has quite a bit of warmth to overcome.
https://i.imgur.com/Zyki57w.png

So we can't see any WWB's and there must be EWB's throughout July.

Well, things are definitely stacked for July not to have a WWB (outside brief 5m/s anomalies), the weak MJO will mean insufficient forcing for WWB activity, and the PMM phase will soon favor EWBs, as well as make WWBs more difficult to come by, by moving them northward away from the equator

The background state can produce WWBs though. Doesn't have to solely be through atmosphere Kelvin waves or the MJO. Interesting about the PMM phase. Any studies that show +PMM's triggering EWB's?

[Kingarabian]

Also remember Ventrice's tweet anout the CFSv2 showing an El Nino standing wave forming over the EPAC?

 https://twitter.com/MJVentrice/status/1141701513397571585




The Euro has been in agreement with the model, and even the GFS to some extent:


We'll see what happens.

[NotSparta]

But we still need to see some sort of cooperation from the atmosphere to see El Nino wash out by the fall. Because we saw the same thing happen around mid May before a WWB came on. There are arguments to be made that this upwelling Kelvin wave is stronger, however it still has quite a bit of warmth to overcome.
https://i.imgur.com/Zyki57w.png

So we can't see any WWB's and there must be EWB's throughout July.

Well, things are definitely stacked for July not to have a WWB (outside brief 5m/s anomalies), the weak MJO will mean insufficient forcing for WWB activity, and the PMM phase will soon favor EWBs, as well as make WWBs more difficult to come by, by moving them northward away from the equator

The background state can produce WWBs though. Doesn't have to solely be through atmosphere Kelvin waves or the MJO. Interesting about the PMM phase. Any studies that show +PMM's triggering EWB's?

Yes, the bgd state can produce WWBs, but usually only one you get into at least moderate Niño range. All the current bgd state can do is cause modestly reduced trades.

I'm not so sure the +PMM can trigger full blown EWBs, but a +PMM's effect in the summer is definitely to cause more -u anomalies. Essentially, the equator becomes like the southern branch of the PMM, meaning enhanced SE trades affect the equator more.

[Kingarabian]

Well, things are definitely stacked for July not to have a WWB (outside brief 5m/s anomalies), the weak MJO will mean insufficient forcing for WWB activity, and the PMM phase will soon favor EWBs, as well as make WWBs more difficult to come by, by moving them northward away from the equator

The background state can produce WWBs though. Doesn't have to solely be through atmosphere Kelvin waves or the MJO. Interesting about the PMM phase. Any studies that show +PMM's triggering EWB's?

Yes, the bgd state can produce WWBs, but usually only one you get into at least moderate Niño range. All the current bgd state can do is cause modestly reduced trades.

I'm not so sure the +PMM can trigger full blown EWBs, but a +PMM's effect in the summer is definitely to cause more -u anomalies. Essentially, the equator becomes like the southern branch of the PMM, meaning enhanced SE trades affect the equator more.

Well this is an interesting development for sure.

[NotSparta]

The background state can produce WWBs though. Doesn't have to solely be through atmosphere Kelvin waves or the MJO. Interesting about the PMM phase. Any studies that show +PMM's triggering EWB's?

Yes, the bgd state can produce WWBs, but usually only one you get into at least moderate Niño range. All the current bgd state can do is cause modestly reduced trades.

I'm not so sure the +PMM can trigger full blown EWBs, but a +PMM's effect in the summer is definitely to cause more -u anomalies. Essentially, the equator becomes like the southern branch of the PMM, meaning enhanced SE trades affect the equator more.

Well this is an interesting development for sure.

We've seen this before, this is why 2018 didn't have the Niño begin to get going in September/October. This time will be more interesting, because this time the WPAC isn't so warm

[Kingarabian]

Yes, the bgd state can produce WWBs, but usually only one you get into at least moderate Niño range. All the current bgd state can do is cause modestly reduced trades.

I'm not so sure the +PMM can trigger full blown EWBs, but a +PMM's effect in the summer is definitely to cause more -u anomalies. Essentially, the equator becomes like the southern branch of the PMM, meaning enhanced SE trades affect the equator more.

Well this is an interesting development for sure.

We've seen this before, this is why 2018 didn't have the Niño begin to get going in September/October. This time will be more interesting, because this time the WPAC isn't so warm

What's driving the PMM right now, the CPAC? Because waters are still cooler than normal W/SW of Baja,

[NotSparta]

Well this is an interesting development for sure.

We've seen this before, this is why 2018 didn't have the Niño begin to get going in September/October. This time will be more interesting, because this time the WPAC isn't so warm

What's driving the PMM right now, the CPAC? Because waters are still cooler than normal W/SW of Baja,

Definitely the CPAC. Because of it, as a whole, the NP is warmer the SP, the definition of a +PMM.

[dexterlabio]

So if this weak El Nino survives this summer, there is a chance for it to strengthen by September?

Idk but understanding the mechanics of ENSO has become challenging since 2012...I mean since that time, we've seen clear signs of EN early in the year only for that year to become La Nina-ish, as well as years when El Nino (or a super El Nino) developing when it seemed not likely to develop.

[Tailspin]

http://www.bom.gov.au/climate/enso/#tabs=Outlooks

Considering that current NINO index values are neutral, indicators in both atmosphere and ocean continue to ease, and model outlooks favour an ENSO-neutral state for the coming months, the Bureau ENSO Outlook has been reset to INACTIVE.
http://i66.tinypic.com/99p5w2.jpg
http://i64.tinypic.com/334846x.png

Note that BOM's definition of El Niño is +0.8°C, it would make sense that that value won't be reached for a while

I sense sarcasm in your post. I'm well aware of the bom's thresholds. Are you suggesting there
will be a nino when a key point in there update is models indicate the tropical Pacific will continue shifting further away from El Niño thresholds through the winter.. Fyi S-H winter.

Obviously you think you have a better knowledge than the PHD academics who work for bom.

[NotSparta]

http://www.bom.gov.au/climate/enso/#tabs=Outlooks

Considering that current NINO index values are neutral, indicators in both atmosphere and ocean continue to ease, and model outlooks favour an ENSO-neutral state for the coming months, the Bureau ENSO Outlook has been reset to INACTIVE.
http://i66.tinypic.com/99p5w2.jpg
http://i64.tinypic.com/334846x.png

Note that BOM's definition of El Niño is +0.8°C, it would make sense that that value won't be reached for a while

I sense sarcasm in your post. I'm well aware of the bom's thresholds. Are you suggesting there
will be a nino when a key point in there update is models indicate the tropical Pacific will continue shifting further away from El Niño thresholds through the winter.. Fyi S-H winter.

Obviously you think you have a better knowledge than the PHD academics who work for bom.

Ah, sorry, wasn't sure if you did. I wasn't trying to be sarcastic

And no, I believe that this ENSO event will continue to weaken, but even in a high end scenario it's unlikely there'd be El Niño based on their metrics

lol I don't. I have a lot to learn, I'm nowhere close to comparing to their knowledge

[SFLcane]

Upwelling oceanic kelvin wave + trade surge over the eastern Pacific for ~2 weeks will result in further cooling at the surface.

[tolakram]

I would really like to see some verification by some of constant sources we see here. I'm not asking for anything to change, but there's so much information, much of it via tweets, and much of it nothing more than educated guesses. Trying to stay as objective as possible is tough but I don't see anything solid to indicate that el nino will end this year. Weak el nino still seems to be the best forecast for the heart of the Atlantic hurricane season. Even if it fades during the fall how long does it take the atmosphere to show the change (less wind shear over the Atlantic for example)?

[chaser1]

I would really like to see some verification by some of constant sources we see here. I'm not asking for anything to change, but there's so much information, much of it via tweets, and much of it nothing more than educated guesses. Trying to stay as objective as possible is tough but I don't see anything solid to indicate that el nino will end this year. Weak el nino still seems to be the best forecast for the heart of the Atlantic hurricane season. Even if it fades during the fall how long does it take the atmosphere to show the change (less wind shear over the Atlantic for example)?

Right; I'm still not convinced that the current pattern is entirely El Nino induced but regardless I've always noticed past waning (warm to neutral) events to result in a several week delay for any newly established regional flow to impact the W. Atlantic. All the recent months of El Nino conjecture have seemed based more on minuscule month to month variances. Doesn't look like anything particularly dramatic changing anytime soon (then again, it is only late June/early July now)

[NotSparta]

I would really like to see some verification by some of constant sources we see here. I'm not asking for anything to change, but there's so much information, much of it via tweets, and much of it nothing more than educated guesses. Trying to stay as objective as possible is tough but I don't see anything solid to indicate that el nino will end this year. Weak el nino still seems to be the best forecast for the heart of the Atlantic hurricane season. Even if it fades during the fall how long does it take the atmosphere to show the change (less wind shear over the Atlantic for example)?

Well, there's nothing solid to indicate El Niño has much time left

It's already near borderline, the subsfc is cooling down, and this is the time where a WWB should have occurred, yet there's nothing.

Just my $0.02 though

[Ntxw]

We will likely see another 0.5C or greater trimonthly here once July hits. Still a weak modoki Nino. If cooling continues JJA is the best shot at going below. That won't be so until the September update. MJJ could do it but I think it will keep the >0.5C.

[Kingarabian]

What I was talking about yesterday:
 https://twitter.com/MJVentrice/status/1143832734076456960



So we are seeing resistance from the atmosphere as evidenced by these persistent -VP200 anomalies over the EPAC and a continued negative SOI.
GFS has anomalously weak trades over the next week which will likely provide temporary cooling relief for SST's over the Nino regions.

[WeatherEmperor]

The CFS continues to lower enso values for regions 3.4 and 3 for peak season in the ATL. It shows 3.4 dropping to warm neutral and 3 dropping to neutral or ever so slightly cool neutral for Aug/Sept. Looks like El Nino would be heavily west based this year as region 4 goes to around +1.0C peak season.








Sent from my iPhone using Tapatalk