2024 ENSO Updates

[cycloneye]

https://www.cpc.ncep.noaa.gov/products/ ... disc.shtml

[Kingarabian]

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

https://i.imgur.com/TyH7GTp.png

Inline with the discussions on here since the start of the season.

[chaser1]

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

https://i.imgur.com/TyH7GTp.png

Inline with the discussions on here since the start of the season.

I'd say that's pretty true. I'm pretty sure that if one were to go back to perhaps February or March however, the expectations were for Nina conditions to begin a bit earlier in the season. Given what I have noticed to be a downstream lag for newly developed ENSO phases over the years, it is my sense that NINA impact to this Atlantic season would then lag roughly 2-4 weeks? If so, further enhanced conditions in the Atlantic may not be realized until perhaps early to mid-September. From that alone, I am anticipating a particularly harsh and active September & October (and a continued November threat to Central America and Mexico).

What I am more curious about is whether or not (or to what extent) the overall longwave pattern might change in response to NINA conditions or other seasonal variations. We already know that overall instability should aid in an increase of tropical activity but I'm more concerned about nuances that may impact changes in the mid-level ridging pattern or affect the Zonal Westerlies flow perhaps causing a higher latitude progressive zonal flow and a decrease in mid latitude trough incursions during this period. Basically, those atmospheric "missile guidance systems" which will ultimately affect storm track patterns.

[Ntxw]

SOI is very low for a La Nina...

[Kingarabian]

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

https://i.imgur.com/TyH7GTp.png

Inline with the discussions on here since the start of the season.

I'd say that's pretty true. I'm pretty sure that if one were to go back to perhaps February or March however, the expectations were for Nina conditions to begin a bit earlier in the season. Given what I have noticed to be a downstream lag for newly developed ENSO phases over the years, it is my sense that NINA impact to this Atlantic season would then lag roughly 2-4 weeks? If so, further enhanced conditions in the Atlantic may not be realized until perhaps early to mid-September. From that alone, I am anticipating a particularly harsh and active September & October (and a continued November threat to Central America and Mexico).

What I am more curious about is whether or not (or to what extent) the overall longwave pattern might change in response to NINA conditions or other seasonal variations. We already know that overall instability should aid in an increase of tropical activity but I'm more concerned about nuances that may impact changes in the mid-level ridging pattern or affect the Zonal Westerlies flow perhaps causing a higher latitude progressive zonal flow and a decrease in mid latitude trough incursions during this period. Basically, those atmospheric "missile guidance systems" which will ultimately affect storm track patterns.

Some of the most memorable Atlantic hurricane seasons occurred when ENSO was cool neutral and transitioning to La Nina late in the season. So IMO, it doesn't get much better than this for an active and memorable season. The only wrinkle is the SOI being in El Nino territory. Meaning that the atmosphere is not yet coupled with the ocean so it may effect somethings downstream.

[Ntxw]

Finally getting some decent +SOI. Perhaps more Nina like-late summer pattern may appear. More favorable for Atlantic activity.

Interestingly relative to normal anoms, 2024 around this time is cooling tropics (not unexpected during Nina for the Pacific) but compared to the high lats the Atlantic and Indian Oceans as well.

[Ntxw]

The Nina transition has occurred much slower than most of us anticipated earlier in the year. The top layer near the surface has held on to warmth (surprised?) longer than you'd typically see in a quick Nina development. The global oceans are warm, and have continued to warm in particular the mid-high latitudes. Our canonical thinking of ENSO likely will have to change. As waters warm in the extra-tropical regions they will inevitably play an ever growing role as the thresholds for sustaining convection moves northward.

[Kingarabian]

30 day SOI flipped positive finally. Atlantic should respond in during the first half of September.

[cycloneye]

CPC in the weekly update has niño 3.4 at 0.0C.

LarryWx, how does the RONI have it?



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

[LarryWx]

CPC in the weekly update has niño 3.4 at 0.0C.

LarryWx, how does the RONI have it?

https://i.imgur.com/227RemN.jpeg

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

Estimated RONI is .-0.6ish, a fairly dangerous level for the corridor from the Lesser Antilles NW to the E GOM including the SE US (not what I want to see but that’s just a general indicator as analogs vary quite a bit).

[Kingarabian]

Although it might be late in the game, the GFS has the MJO going strong over the MC. As a result it shows a very significant dateline trade burst.

[cycloneye]

The weekly CPC update has niño 3.4 going down to -0.2C and niño 3 down to -0.5C.



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

[Ntxw]

Really late to only be getting -0.2C. Weak Nina may be the ceiling now.

Other note, the global TC ACE continues to be below normal. Seems to be plaguing all basins (though the Atlantic had a hot start.) While I wouldn't consider 2013 an analog, I would definitely revisit the circumstances that caused the global slowing of tropical activity as well as the weaker -ENSO. All this in a similar -PDO mode that killed the 2012 El Nino potential. 2023 did have an El Nino but not completely all of the typical El Nino behaviors.

[SconnieCane]

Really late to only be getting -0.2C. Weak Nina may be the ceiling now.

Other note, the global TC ACE continues to be below normal. Seems to be plaguing all basins (though the Atlantic had a hot start.) While I wouldn't consider 2013 an analog, I would definitely revisit the circumstances that caused the global slowing of tropical activity as well as the weaker -ENSO. All this in a similar -PDO mode that killed the 2012 El Nino potential. 2023 did have an El Nino but not completely all of the typical El Nino behaviors.

I thought 2011-12 featured a powerful La Nina which was correlated with the extremely violent tornado activity of spring 2011 and the exceptionally warm/snowless winter which led to the anomalously warm early spring and scorching summer of 2012. However apart from featuring Irene and Sandy, I don't recall anything exceptional about those two hurricane seasons.

[Kingarabian]

Really late to only be getting -0.2C. Weak Nina may be the ceiling now.

Other note, the global TC ACE continues to be below normal. Seems to be plaguing all basins (though the Atlantic had a hot start.) While I wouldn't consider 2013 an analog, I would definitely revisit the circumstances that caused the global slowing of tropical activity as well as the weaker -ENSO. All this in a similar -PDO mode that killed the 2012 El Nino potential. 2023 did have an El Nino but not completely all of the typical El Nino behaviors.

I thought 2011-12 featured a powerful La Nina which was correlated with the extremely violent tornado activity of spring 2011 and the exceptionally warm/snowless winter which led to the anomalously warm early spring and scorching summer of 2012. However apart from featuring Irene and Sandy, I don't recall anything exceptional about those two hurricane seasons.

2012 had a petty serious El Nino fake that fizzled out in June.

[Kingarabian]

Really late to only be getting -0.2C. Weak Nina may be the ceiling now.

Other note, the global TC ACE continues to be below normal. Seems to be plaguing all basins (though the Atlantic had a hot start.) While I wouldn't consider 2013 an analog, I would definitely revisit the circumstances that caused the global slowing of tropical activity as well as the weaker -ENSO. All this in a similar -PDO mode that killed the 2012 El Nino potential. 2023 did have an El Nino but not completely all of the typical El Nino behaviors.

Weak and late La Nina is probably the best bet right now.

[Iceresistance]

90 Day SOI is now positive

[Ntxw]

90 Day SOI is now positive

Aleutian ridge in the medium range is supported by the rising SOI. So far it's been looking like an "eastern" lean based La Nina. I quote this because unlike El Nino, the effects are not as profound compared to canonical vs modoki El Nino.

[Kingarabian]

Buoys continue to show lackluster -anomalies down to 100m. Very odd.

Upwelling KW setting up below the WPAC. Let's see if this one can intensify and move east to trigger La Nina by this winter.

[Kingarabian]

NIno 4: 0.2ºC
Niño 3.4: -0.1ºC
Niño 3: -0.2ºC
Niño 1+2: -0.4ºC
This weeks updates.