ENSO Updates (2007 thru 2023)

[stormwise]

moderate

[Siker]

 https://twitter.com/Climatologist49/status/762758265818091520

[cycloneye]

Very interesting development.Let's see how the monthly July data responds in a few days.The June reading was +2.03.

[Ntxw]

July will be high still looking at that chart because most of the time was well over.

Though to be honest I am skeptical of a 'daily' PDO index because the nature of a PDO reading is over much larger timescale, even more than ENSO

[Kingarabian]

A daily PDO index is pretty much pointless. Because even the monthly index may be too much when you take into consideration that the PDO is a long term oscillation.

[Hunabku]

One can see the deepening of subsurface cooling likely caused by all the recent 3.4 focused trades.



Looks like nearly a month of solid trades might be ending soon - however temporarily?

[Kingarabian]

Lots of trades... very cool at the subsurface.

Yet no significant cooling at the subsurface? Why?

[Hunabku]

:uarrow: Lots of trades... very cool at the subsurface.

Yet no significant cooling at the subsurface? Why?

In places where they were the strongest (cumulatively over the month), the trades seemed to have stopped the subsurface warming trend and even reverse it. Without solid nina atmospheric response the cold pool eventually goes away. Perhaps we have entered a positive decadal phase of ENSO where the atmosphere is less likely to couple with the ocean in a negative or nina way. Notice how i left the PDO out of this intentionally.

Edit: A wildcard in all this has been the MJO. It seemed anomalously active during the winter-time of this nino and it also disrupted the trades during the developing nina phase. Here is an interesting research letter on the topic published in 2014: Disruptions of El Niño–Southern Oscillation Teleconnections by the Madden–Julian Oscillation http://onlinelibrary.wiley.com/doi/10.1002/2013GL058648/full

Oh and I found this one even more informative: The relationship between intraseasonal tropical variability and ENSO and its modulation at seasonal to decadal timescales https://hal.archives-ouvertes.fr/hal-00994186/document

In particular, it has been noticed that the occurrence of the non-conventional El Niño (i.e. Central Pacific El Niño) has been increasing since 1990 [4, 41, 87], which has been argued to be related to the mean state changes in the tropical Pacific and ENSO feedback processes [87]. Our results indicate that such trends could also be related to changes in the intraseasonal tropical variability/ENSO relationship. This is the topic of current research.

[Ntxw]

Jisao hasn't updated yet, but NCDC's value is +0.18 for July. June was 0.75 and was 2.03 with Jisao. I'm guessing it will come in around +1 to +1.25. The downtrend continues but will still be positive making 2016 a +PDO year.

[cycloneye]

 https://twitter.com/NWSCPC/status/763736664695009280

[Kingarabian]

Great article from Emily Becker @ Climate.gov on the current status of ENSO:

https://www.climate.gov/news-features/b ... wavy-gravy

She goes into more detail about the tropical instability waves that may be slowing La Nina.

[Ntxw]

The fact that the probability is almost 1 in 2 shows the disparity in the possibility of an established La Nina. During this period is when solid events are maturing and odds are greater than not. We are not spring anymore and approaching fall. Most solid Nina's and Nino's are usually nearing 80-100% odds.

[chaser1]

The fact that the probability is almost 1 in 2 shows the disparity in the possibility of an established La Nina. During this period is when solid events are maturing and odds are greater than not. We are not spring anymore and approaching fall. Most solid Nina's and Nino's are usually nearing 80-100% odds.

Maybe an indication that what ultimately plays out for the Fall/Early Winter months is a prolonged Neutral to weak LaNina period, before perhaps a much delayed but eventual stronger LaNina event months later? Regardless and even if that played out, I would'nt think this to have much effect on our Atlantic hurricane season. SAL or other factors aside, a weak La Nina still factors in as being favorable with regards to cyclone genesis and activity.

[Ntxw]

The fact that the probability is almost 1 in 2 shows the disparity in the possibility of an established La Nina. During this period is when solid events are maturing and odds are greater than not. We are not spring anymore and approaching fall. Most solid Nina's and Nino's are usually nearing 80-100% odds.

Maybe an indication that what ultimately plays out for the Fall/Early Winter months is a prolonged Neutral to weak LaNina period, before perhaps a much delayed but eventual stronger LaNina event months later? Regardless and even if that played out, I would'nt think this to have much effect on our Atlantic hurricane season. SAL or other factors aside, a weak La Nina still factors in as being favorable with regards to cyclone genesis and activity.

Its possible, but 2017 is just too far away to guess right now. Weak Nina and neutrals just dont provide shear like Nino's so they are more conducive. But they are not always as favorable as a stronger event. There is more to it than shear, you are looking at the globe as a whole and placement of the walker cell, ridge/trough placement for an entire season. Its more likely you see a very hyper type season with a mod to strong La Nina. As with weaker events you depend on whatever the background state in the Atlantic is. There are active weaker events but there are equally as many inactive. While a stronger Nina there are far more very active seasons than not, less uncertainty.

[Ntxw]

-0.6C this week. Still hovering around similar values

[cycloneye]

Text of CPC update of 8/15/16 that has Nino 3.4 at -0.6C.

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

[Ntxw]

PDO for July came in at +1.25

[cycloneye]

PDO for July came in at +1.25

Umm good drop from the June +2.03C.

[Kingarabian]

PDO for July came in at +1.25

1.25+ is still a pretty warm reading.

Unless we see rapid and stronger cooling, I think the PDO will stay between +0.60-1.00+ for the rest of the year.

[stormwise]

I get 0.18 @ https://www.ncdc.noaa.gov/teleconnections/pdo/