ENSO Updates (2007 thru 2023)

[DorkyMcDorkface]

Quick subsurface comparison between now and the last time we had a developing Niño (2019). Goes without saying that we are definitely ahead of that year up to this point, as in, it's not even particularly close. Makes sense with how late developing and weak the 2019-20 event ultimately was. And mind you 2019 had a very potent WWB in February (the one that generated Wutip), but the episodes we've seen thus far this year haven't resulted in any real WPAC/SEPAC activity outside of a weak TS in the former, although I am expecting that to change. I think it speaks to how much warmth can gather in the subsurface during a triple-dip Niña. We are already seeing the magnitude of the warm pool with how strong the positive anoms in the 1+2 regions have been. Now we await for 3.4 to start climbing.

[dexterlabio]

Quick subsurface comparison between now and the last time we had a developing Niño (2019). Goes without saying that we are definitely ahead of that year up to this point, as in, it's not even particularly close. Makes sense with how late developing and weak the 2019-20 event ultimately was. And mind you 2019 had a very potent WWB in February (the one that generated Wutip), but the episodes we've seen thus far this year haven't resulted in any real WPAC/SEPAC activity outside of a weak TS in the former, although I am expecting that to change. I think it speaks to how much warmth can gather in the subsurface during a triple-dip Niña. We are already seeing the magnitude of the warm pool with how strong the positive anoms in the 1+2 regions have been. Now we await for 3.4 to start climbing.
https://i.ibb.co/VQpjJYw/dep-lon-EQ-20190426-t-anom-20230426-t-anom-500-0-500-0-hf-2023042908.png

I thought the WWB favored TC genesis in the SHem instead (Ilsa).

[DorkyMcDorkface]

Quick subsurface comparison between now and the last time we had a developing Niño (2019). Goes without saying that we are definitely ahead of that year up to this point, as in, it's not even particularly close. Makes sense with how late developing and weak the 2019-20 event ultimately was. And mind you 2019 had a very potent WWB in February (the one that generated Wutip), but the episodes we've seen thus far this year haven't resulted in any real WPAC/SEPAC activity outside of a weak TS in the former, although I am expecting that to change. I think it speaks to how much warmth can gather in the subsurface during a triple-dip Niña. We are already seeing the magnitude of the warm pool with how strong the positive anoms in the 1+2 regions have been. Now we await for 3.4 to start climbing.
https://i.ibb.co/VQpjJYw/dep-lon-EQ-20190426-t-anom-20230426-t-anom-500-0-500-0-hf-2023042908.png

I thought the WWB favored TC genesis in the SHem instead (Ilsa).

Ilsa was western AUS region in the Indian Ocean, though? That's a different region - you won't get TCG spurred by Pacific WWBs there, it would need to be an IO WWB, and even then I think Ilsa was too far to the SE for that.

[Yellow Evan]

AUS is directly below the WPAC in longitude so sometimes you get twin TC’s in those 2 basins. Andy/Orson from 1989 is the famous example. Hell Ilsa’s WPAC twin (90W) probably should have been designated.

[DorkyMcDorkface]

:uarrow: AUS is directly below the WPAC in longitude so sometimes you get twin TC’s in those 2 basins. Andy/Orson from 1989 is the famous example. Hell Ilsa’s WPAC twin (90W) probably should have been designated.

I'm mistaken then, I guess I underestimate the true scope of the WPAC basin and how much territory it takes up. The basin's MDR essentially extends to what, 125-130E or so (just east of the Philippines)? I'm guessing the South China Sea is excluded, but regardless that's a lot of real estate.

[cycloneye]

:uarrow: AUS is directly below the WPAC in longitude so sometimes you get twin TC’s in those 2 basins. Andy/Orson from 1989 is the famous example. Hell Ilsa’s WPAC twin (90W) probably should have been designated.

I'm mistaken then, I guess I underestimate the true scope of the WPAC basin and how much territory it takes up. The basin's MDR essentially extends to what, 125-130E or so (just east of the Philippines)? I'm guessing the South China Sea is excluded, but regardless that's a lot of real estate.

WPAC goes from the dateline to 100E and that includes the SCS.

[DorkyMcDorkface]

:uarrow: AUS is directly below the WPAC in longitude so sometimes you get twin TC’s in those 2 basins. Andy/Orson from 1989 is the famous example. Hell Ilsa’s WPAC twin (90W) probably should have been designated.

I'm mistaken then, I guess I underestimate the true scope of the WPAC basin and how much territory it takes up. The basin's MDR essentially extends to what, 125-130E or so (just east of the Philippines)? I'm guessing the South China Sea is excluded, but regardless that's a lot of real estate.

WPAC goes from the dateline to 100E and that includes the SCS.

https://i.imgur.com/HSf1jLO.gif

Yeah I know the basin as a whole extends to the SCS but I'm talking about approximating a main development region like what we have in the Atlantic. I guess it's harder to pinpoint since the WPAC tropics are like 2-3 times the size of the NATL but dateline to east of the Philippines was what I was roughly thinking in terms of where an "MDR" would be (if there is one) since that is where TCG appears to be most common.

...sorry, have I veered off topic?

[Yellow Evan]

Mariana Islands to the Philippines is probably the best answer to the above question. I believe the initial disturbance that spawned Ilsa was around 130E.

[dexterlabio]

There was a spring WWB event back in 2014 that also spawned an intense SHem cyclone (Ita).

Speaking of WWB and WPAC, I wonder if we will get our first pre-El Nino STY in May.

[Kingarabian]

Nino 1.2 should come down to earth in the next 2 weeks. Solid trades from 180-100E.

[Kingarabian]

There was a spring WWB event back in 2014 that also spawned an intense SHem cyclone (Ita).

Speaking of WWB and WPAC, I wonder if we will get our first pre-El Nino STY in May.

Euro has a decent WWB over the WPAC in less than 2 weeks. That could be the time.

[jconsor]

Reasons for little eastward progression of the WWB in the western Pacific through early May.

 https://twitter.com/NDGMETCHEF/status/1652725034161414149




 https://twitter.com/yconsor/status/1652748795371724803

[Category5Kaiju]

Reasons for little eastward progression of the WWB in the western Pacific through early May.

https://twitter.com/NDGMETCHEF/status/1652725034161414149

https://twitter.com/yconsor/status/1652748795371724803

At this point I think we can safely rule out a super Nino; as mentioned in that thread you need continuous, powerful westerlies in May to get that sort of setup.

[cycloneye]

CPC weekly update has Niño 3.4 up to +0.4C and is on the brink of the threshold of El Niño of +0.5C.

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

[dexterlabio]

I dont know but the ongoing trades in the EPAC doesn't look to be a step backward since this is already expected when the MJO passes through IO, and it's not like the MJO will overstay in the region like what usually happens in a La Niña year.

And if I'm not mistaken the last time the MJO went over IO, it didn't do that much to reverse the warming of the Niño regions, but granted the signal went to the circle before it reached the Maritime Continent.

[Kingarabian]

The only thing limiting the strength of this upcoming El Nino event is the Atlantic and Africa.

[zzzh]

Also the -PDO, -PMM.

[Iceresistance]

:uarrow: Also the -PDO, -PMM.

Is there a site for me to track the PMM and/or the AMM?

[zzzh]

:uarrow: Also the -PDO, -PMM.

Is there a site for me to track the PMM and/or the AMM?

https://psl.noaa.gov/data/timeseries/monthly/PMM/
https://psl.noaa.gov/data/timeseries/monthly/AMM/

[cycloneye]

 https://twitter.com/philklotzbach/status/1653075726504165377