ENSO Updates (2007 thru 2023)

[Ntxw]

Folks El Nino is here. Looking at sea surface anomalies and SOI's persistent negatives most of June and now July no doubt El Nino is here and will be declared soon if not today. If this idea stands July will be the first month in which we see the tropical regions be effected by El Nino.

[wxman57]

Actually, I believe there has to be a 3 month average (for a 5 month period?) of El Nino conditions before it is declared "official". However, its effects will be felt during peak season in August and September.

[Ntxw]

Actually, I believe there has to be a 3 month average (for a 5 month period?) of El Nino conditions before it is declared "official". However, its effects will be felt during peak season in August and September.

90 day SOI is reflective of that trimonthly wxman. Once it approaches the -8 threshold it's not inconceivable that June/July/August will be our first Nino trimonthly.

[joshb19882004]

the atmosphere is lagging behind right now although the el nino pattern is present noaa in todays update said that the atmosphere reflects cool to neutral

[LarryWx]

Actually, I believe there has to be a 3 month average (for a 5 month period?) of El Nino conditions before it is declared "official". However, its effects will be felt during peak season in August and September.

That is correct..five trimonthly averages in a row of +0.5 C Nino 3.4 anomaly or warmer is the minimum for El Nino to be officially declared. Therefore, it can't be officially declared until well after it starts in retrospect. Based on the recent pretty sharp SST rises in 3.4 (now at +0.6 C) along with the persistent solid -SOI (also OHC anomalies have risen further in June vs. May), I'm educatedly guessing that JJA will, in retrospect be the start, trimonthlywise, of an official El Nino. If that turns out to be the case, it technically couldn't actually be declared until after OND is determined (at the end of the 5th trimonth), which would be ~1/1/13. Assuming that occurs, the Nino would have started in retrospect in JJA or about now. In other words, we'd in retrospect now be at about the start of El Nino assuming the +0.5+ 3.4 SST's end up persisting. In reality, we'd pretty much know with a lot of confidence well before OND. There's no sense forecastingwise in waiting until 1/1/13. We might as well now assume we're likely at about the start of El Nino, especially considering what the ENSO models are showing.

[cycloneye]

Climate Prediction Center 7/2/12 Update/Nino 3.4 reaches El Nino threshold

This update is very important because Nino 3.4 has reached El Nino threshold of +0.5C.In fact it went up to +0.6C

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

[euro6208]

mmm the mjo is expected to return to the western hemisphere combined with high pressure over australia (more tanking of soi), looks like this el nino might be a strong one...

[joshb19882004]

could it be possible for el nino to get strong with a cold pdo in a short amount of time

[KWT]

Actually, I believe there has to be a 3 month average (for a 5 month period?) of El Nino conditions before it is declared "official". However, its effects will be felt during peak season in August and September.

Yeah, we'll probably be in the 'moderate' range by September, think it may well be an early ending season.

[Blown Away]

Does this years pattern resemble an El Nino year of the past?

[cycloneye]

Here is how the 30 day SOI has behaved since 1800 to present. The big question is how strong this El Nino will be.

[Ntxw]

Does this years pattern resemble an El Nino year of the past?

Not in terms of named systems or much in the way of tropics (though majority of NATL basin has been dominated by subtropical systems in nature), but overall global patterns and enso evolution 2002 is becoming one of the heavy weights.

[NDG]

Weird that today's graphic update shows a slight cool down at Nino 3.4 Region from a week ago.

[Ntxw]

Weird that today's graphic update shows a slight cool down at Nino 3.4 Region from a week ago.

Nino 4 held steady maybe even slightly cool but 3 rose significantly which is what brought 3.4 over. 3.4 is a composite of 3 and 4 regions with 3 having a larger chunk

[hurricanetrack]

Weak to mod El Nino against a cold PDO. Will be interesting to what THAT outcome is. Also, ATL not too shabby in deep tropics. Certainly not significantly cooler than normal and the tropical waves seem to be doing just fine for this time of year.

[NDG]

Weak to mod El Nino against a cold PDO. Will be interesting to what THAT outcome is. Also, ATL not too shabby in deep tropics. Certainly not significantly cooler than normal and the tropical waves seem to be doing just fine for this time of year.

And to add to that a persistent neutral to negative NAO over the last couple of months, maybe the reason why the atmosphere is still lagging behind with similarities to a cool to neutral ENSO.

[LarryWx]

Weird that today's graphic update shows a slight cool down at Nino 3.4 Region from a week ago.

In addition to what was stated about the eastern 3.4 warming while the western 3.4 may have cooled, you're comparing 7/2 with 6/25. During that time, it does look as if the western 3.4 cooled although eastern 3.4 looks to have warmed (i.e., maybe about a wash). In reality, however, the weekly Nino SST releases are based on the average for the prior calendar week. So, today's release is actually based on the average of 6/24-30. The prior release, that from 6/25, is actually based on the average of 6/17-23. So, the proper comparison would be the avg. of 6/24-30 vs. the avg. of 6/17-23. If those two averages were compared, it may very well be that 6/24-30 would clearly look warmer than 6/17-23 in Nino 3.4.

[joshb19882004]

the neutral to -nao maybe also responsable for the massive heat wave over the central and eastern sections of the U.S

[hcane27]

Does this years pattern resemble an El Nino year of the past?

Currently the pattern from January thru May in Nino 3-4 most closely resembles 1951 , 2006 , and 2009

[Kingarabian]

Does this years pattern resemble an El Nino year of the past?

Currently the pattern from January thru May in Nino 3-4 most closely resembles 1951 , 2006 , and 2009

Not so sure about 2009.

2009's El-Nino was really strong and it suppressed all activity in the Atlantic basin.