ENSO Updates (2007 thru 2023)

[Kingarabian]

 https://twitter.com/Met_mdclark/status/989814647640461312




That area of anomalous westerly winds in the EPAC on the Euro forecast continues to gain traction. Coincides with the SOI being negative for at least the first week of May. This is not showing up on the GFS 850mb wind graphic right now due to the GFS consistently having the wrong pressures over Australia for the past few days. Not sure what the model is currently seeing or doing. In the short term, the moderate/strong WWB just west of the dateline will continue to enforce the subsurface warm pool.

Later on in the forecast, the trades are shown to re intensify due to the Euro trying to push the MJO into phases 2&3 and thus a positive SOI setup. But I would proceed with caution because the Euro hasn't handled the MJO particularly well so far this year.

[Kingarabian]

I certainly agree El Nino is not a foregone conclusion. In fact most here agree some sort of neutral the next few months is likely. What we are discussing is the progression of the Ocean and atmosphere and what it *MAY* do down the road beyond just what implications it may portray more than just the Atlantic hurricane season, as some here tends to base it by. We've seen some foundation shifts toward building an El Nino but there are stumbling blocks.

2009 is brought up because it has the closest set up to today. It does not mean we will achieve what 2009 did. If you see a better year we're all open to analogs!

Even with 2009 being a close comparison, in 2009 we did not have strong successive WWB's west of the dateline throughout the spring like this year has had so far. That's why the warm sub surface pool is stronger this year compared to 2009(I know its not close to 2014/2015 levels).

[Kingarabian]

April 22:

[tweet]https://twitter.com/webberweather/status/98815367135878758[tweet]

Also at the same time the latest Euro run for the next 9 days would bring down the April 30 day SOI average from +8.5 to +3.0.

Have to give it to the Euro, it almost completely nailed the SOI drop that far out. April finished at +4.0 on the 30 day SOI average.

Continues to have a negative SOI through May 7.

[Kingarabian]

Shows that 2009 comparisons are warranted.

 https://twitter.com/BenNollWeather/status/989847421067776000




 https://twitter.com/BenNollWeather/status/989848230203613185

[Ntxw]

At the update later this morning will be 0.0C

[cycloneye]

CPC weekly update for Niño 3.4 is now at dead Neutral (0.0C) and that is warmer than the -0.2C that was in last week's update. For sure when the diagnostic CPC update comes out on the 10th of May,they will end La Niña Advisory and add El Niño Watch.

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

[NotSparta]

CPC weekly update for Niño 3.4 is now at dead Neutral (0.0C) and that is warmer than the -0.2C that was in last week's update. For sure when the diagnostic CPC update comes out on the 10th of May,they will end La Niña Advisory and add El Niño Watch.

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

Hmm. I still see last week's update

[LarryWx]

CPC weekly update for Niño 3.4 is now at dead Neutral (0.0C) and that is warmer than the -0.2C that was in last week's update. For sure when the diagnostic CPC update comes out on the 10th of May,they will end La Niña Advisory and add El Niño Watch.

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

Hmm. I still see last week's update

Today's update of a warming of 3.4 to 0.0 is there. Meanwhile, it shows the subsurface having topped for now with a very slight cooling back from +0.9 to +0.8. As we go through the next few months, it will be interesting to see whether or not further significant warming resumes since that often is a precursor to what the 3.4 surface, itself, does. As it stands now, the subsurface is favoring further warming of the 3.4 surface over the next couple of months, overall, and we MAY get weak El Niño by late summer.

[cycloneye]

CPC weekly update for Niño 3.4 is now at dead Neutral (0.0C) and that is warmer than the -0.2C that was in last week's update. For sure when the diagnostic CPC update comes out on the 10th of May,they will end La Niña Advisory and add El Niño Watch.

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

Hmm. I still see last week's update

I had to go out of internet so I posted the link before they changed to the new update around 9 AM EDT.

[Ntxw]

I tend to agree we have topped off the subsurface for now and OHC has leveled. The warming should slow for May. Much like in 2009 it took until late June to head into El Nino territory. I don't know if we will get there but it's clear we have entered neutral. For the next 2-3 months, in theory, I think 0.3C to 0.5C is the range we will be for the first half of summer in the weeklies.

[LarryWx]

I tend to agree we have topped off the subsurface for now and OHC has leveled. The warming should slow for May. Much like in 2009 it took until late June to head into El Nino territory. I don't know if we will get there but it's clear we have entered neutral. For the next 2-3 months, in theory, I think 0.3C to 0.5C is the range we will be for the first half of summer in the weeklies.

We've had 5 weeks in a row of Nino 3.4 warming. The record longest # of weeks in a row of 3.4 warming going back to 1990 is only 7 (May-July 2003) and there have been only a couple of 6 week warming streaks. So, just based on stats, the warming should shortly cease at least temporarily.

[Kingarabian]

I tend to agree we have topped off the subsurface for now and OHC has leveled. The warming should slow for May. Much like in 2009 it took until late June to head into El Nino territory. I don't know if we will get there but it's clear we have entered neutral. For the next 2-3 months, in theory, I think 0.3C to 0.5C is the range we will be for the first half of summer in the weeklies.

We've had 5 weeks in a row of Nino 3.4 warming. The record longest # of weeks in a row of 3.4 warming going back to 1990 is only 7 (May-July 2003) and there have been only a couple of 6 week warming streaks. So, just based on stats, the warming should shortly cease at least temporarily.

There might be a fighting chance we get to 6 weeks in a row of straight warming. I think you or someone pointed out that there is some correlation between a dropping SOI and raising Nino 3.4 values. Very likely we see another week of negative SOI values per the Euro.

[tolakram]

Rewind to May 1st 2017.

viewtopic.php?f=31&t=92137&start=7720

Clarity started mid to late May IMO, this is the fun part of the year before the season begins.

[Ntxw]

This is mostly regarding the low frequency background forcing from his tweet

 https://twitter.com/MJVentrice/status/991333010837516289




Mostly near the IDL and northern latitudes

[LarryWx]

Both. By the way, I decided to take a closer look at the latest guidance and it is close to what you said for tomorrow with no more than a slight rise, if any. However, it also shows a rise to near -10 on 6/5-6. But even that says it won't approach or go barely above 0 like I thought it might for 1-2 days. So, a pretty lengthy (say 10+ days total) unbroken -SOI streak looks likely. The Darwin SLP appears likw it will max out ~1015 ~one week from today. That's pretty high vs climo. Anything above 1014 mb is safely higher than avg there I believe for June.

Darwin: http://www.bom.gov.au/products/IDD60801 ... 4120.shtml

Tahiti: https://www.wunderground.com/history/ai ... .wmo=91938

Thanks!

I just did some calcs based on 1981-2016 that you may find interesting:

Avg June/July/Aug Darwin SLP minus 1000: 13.0/13.5/13.5
Avg June/July/Aug Tahiti SLP minus 1000: 13.7/14.3/14.6

Avg June/July/Aug Darwin SLP minus 1000 strong Nino: 13.5/14.4/14.6
Avg June/July/Aug Darwin SLP minus 1000 wk-mod Nino: 13.0/13.8/13.7
Avg June/July/Aug Darwin SLP minus 1000 weak Nina: 13.0/13.0/12.8
Avg June/July/Aug Darwin SLP minus 1000 mod-str Nina: 12.8/13.1/12.9

Avg June/July/Aug Tahiti SLP minus 1000 strong Nino: 12.8/13.4/13.6
Avg June/July/Aug Tahiti SLP minus 1000 wk-mod Nino: 13.5/13.9/13.7
Avg June/July/Aug Tahiti SLP minus 1000 weak Nina: 14.2/14.3/15.1
Avg June/July/Aug Tahiti SLP minus 1000 mod-str Nina: 14.1/15.2/15.2

s
Some analysis of these #'s:

- At Darwin, SLP differences from one ENSO cat. to another are greater in July than June and even greater in Aug. Perhaps this means that in Nino's that avg. Australian sfc highs are stronger and/or extend further north in July/Aug vs June whereas in Nina's they stay about the same through that period?

- At Tahiti, SLP differences from one ENSO cat. to another are much greater in June than the rather narrow range for Darwin. So, perhaps this means that Tahiti is more crucial than Darwin in June. These diffs from one ENSO cat to another rise more in July from June.

- SLP averages higher in Darwin than Tahiti in strong Ninos, they average ~same in weak to mod Ninos, and are clearly higher at Tahiti than Darwin in Ninas. ALL years combined incl neutral ENSO average nearly 1 mb higher at Tahiti than Darwin. This is probably near where neutral years, alone, fall. That is why the SOI is near 0 when Tahiti is ~1 mb higher than Darwin.

- When I refer to ENSO cat., I mean the upcoming fall/winter peak as opposed to where it is during JJA.
***EDITED***

The above listed Tahiti/Darwin SLP stats should come in handy in June-August to help give us some idea of where ENSO is headed. As the stats suggest, Tahiti SLP looks like it may be more significant than Darwin in June due to its wider spread of averages between ENSO
categories. Regardless, they are just guidelines/averages. I'll try to remember to bump these again as we approach June.

[Kingarabian]

Great call with these numbers, as in the end they held true and determined that we will not see an El Nino in 2017.

I know May has too much variation in pressure to be used as a barometer. But So far based on the 12z Euro, I have on average Tahiti @ 1014.20 and Darwin @ 1012.75 for the first 10 days of May. Euro shows pressures increasing again past 10 days over Darwin and lowering over Tahiti due to MJO progression.

[cycloneye]

@BigJoeBastardi
Signs of the upcoming (IMO) weak modoki type el nino can be seen with falling SOI and warm water lurking underneath the surface. West wind bursts will mean that warmer water will show up on surface later summer into next winter

 https://twitter.com/BigJoeBastardi/status/991627329184071680

[cycloneye]

Webb makes a bold prediction.

@webberweather
This might sound far fetched atm, but there's actually a legitimate chance we see the coveted weak-mod "modoki" NINO/EQBO/low solar combo for the winter of 2018-19. Maybe all those E US snow weenies/blind squirrels who wishcast this configuration every single year will find a nut

 https://twitter.com/webberweather/status/992102872019062784

[Kazmit]

That would be very interesting. That creates much more favorable conditions over the atlantic than a regular El Niño, right? Something to look out for.

[Ntxw]

His tweet is basically putting a carrot to bait 2009, the last low solar eqbo Nino