ENSO Updates (2007 thru 2023)

[Kingarabian]

Yeah the GFS backed way off of the WWB. Mostly had it because of twin TCs which it doesn't show anymore. However, looks like that region will have relaxed trades. East of the dateline, trades remain strong, reinforcing Modoki signature

Massive spread between the models in regards to the MJO so its tough to know if there will be a WWB or not. The Euro and GFS forecast erratic movement of the MJO showing it retrograding while the CFS shows progression into phase 6 and 7. Just have to wait and see.

I'll lean on GFS/ECMWF. It's been difficult to trust the CFS, and it doesn't help it's got known biases that'll move things that way

There's a large difference between the GFS and Euro as well. GFS is closer to the CFS than it is to the Euro.

[floridasun78]

so we going have neutral during hurr season ?

[Kingarabian]

https://twitter.com/cyclonicwx/status/1140616529345748993

Yeah looks really weird. Kudos to the CFS for sniffing out this prolonged EWB a month in advance.

[dexterlabio]

Someone commented about the WPAC being unusually quiet in spite of the El Nino (but I couldn't find the post anymore).

I did some research on this (which I already posted on the 2019 WPAC Season thread) and I listed those years with consecutive mild El Nino events since 1965: 1968-1969, 1976-1977, and 1986-1987. In those pairs, the second year with weak El Nino had less active WPAC season than the year preceding it. In fact, 1969 and 1977 are among the least active WPAC seasons since record-keeping began.

Given that 2019 is shaping up to be a continuation of last year's weak El Nino, there could be a possibility that the WPAC season this year will be less active than 2018, if not a below average season in general.

[Kingarabian]

Someone commented about the WPAC being unusually quiet in spite of the El Nino (but I couldn't find the post anymore).

I did some research on this (which I already posted on the 2019 WPAC Season thread) and I listed those years with consecutive mild El Nino events since 1965: 1968-1969, 1976-1977, and 1986-1987. In those pairs, the second year with weak El Nino had less active WPAC season than the year preceding it. In fact, 1969 and 1977 are among the least active WPAC seasons since record-keeping began.

Given that 2019 is shaping up to be a continuation of last year's weak El Nino, there could be a possibility that the WPAC season this year will be less active than 2018, if not a below average season in general.

Very interesting, thanks for sharing. Is it the same for the EPAC?

[dexterlabio]

Very interesting, thanks for sharing. Is it the same for the EPAC?

Whoa I just did a quick reading and sure this is interesting, 1969 and 1977 are also among the least active EPAC seasons. But the 1987 EPAC season is pretty much average, just like in WPAC. (EDITED: 1987 is in fact more active than 1986 in EPAC so this "theory" doesn't hold true for this pair)

[Chris90]

Someone commented about the WPAC being unusually quiet in spite of the El Nino (but I couldn't find the post anymore).

I did some research on this (which I already posted on the 2019 WPAC Season thread) and I listed those years with consecutive mild El Nino events since 1965: 1968-1969, 1976-1977, and 1986-1987. In those pairs, the second year with weak El Nino had less active WPAC season than the year preceding it. In fact, 1969 and 1977 are among the least active WPAC seasons since record-keeping began.

Given that 2019 is shaping up to be a continuation of last year's weak El Nino, there could be a possibility that the WPAC season this year will be less active than 2018, if not a below average season in general.

Very interesting, thanks for sharing. Is it the same for the EPAC?

Some quick research:
1968 was more active than 1969 in the EPAC, but I'm not fully trusting of those stats that far back for this basin, but we'll assume that the data is decently reliable and say yes, 1969 was less active than the year before.

1976: 15/9/5
1977: 8/4/0

So 1977 was quite a bit less active than '76.

1986: 17/9/3
1987: 20/10/4

1987 ended up being more active than '86, so this doesn't hold true for all those pairs.

It'll be interesting to see how the WPAC and the EPAC end up this year.

[Ntxw]

Just throwing this out there, things can turn on a dime, but despite the mjo movement the past few months has been lacking ACE globally. In short maybe all basins will end up below average. One of "those" years where the Earth just doesn't produce.

Again not saying that will happen but food for thought.

Daily soi is neg again

[TheStormExpert]

Just throwing this out there, things can turn on a dime, but despite the mjo movement the past few months has been lacking ACE globally. In short maybe all basins will end up below average. One of "those" years where the Earth just doesn't produce.

Again not saying that will happen but food for thought.

Daily soi is neg again

So we could see another 2013 in terms of activity even for the Atlantic?

[NotSparta]

Just throwing this out there, things can turn on a dime, but despite the mjo movement the past few months has been lacking ACE globally. In short maybe all basins will end up below average. One of "those" years where the Earth just doesn't produce.

Again not saying that will happen but food for thought.

Daily soi is neg again

So we could see another 2013 in terms of activity even for the Atlantic?

I think that yr the Atlantic suffered from worldwide inactivity and intrabasin problems which made for even less activity

Also, I'm not saying this'll happen, but didn't 2017 start the same way too?

[Ntxw]

Just throwing this out there, things can turn on a dime, but despite the mjo movement the past few months has been lacking ACE globally. In short maybe all basins will end up below average. One of "those" years where the Earth just doesn't produce.

Again not saying that will happen but food for thought.

Daily soi is neg again

So we could see another 2013 in terms of activity even for the Atlantic?

2013 is an anomaly likely a global shift (AO/NAO and EPO/PDO) that threw a curveball. Despite June not being a busy month for any basin really, just food for thought. MJO has a tendency to spur activity, but if it doesn't consistently then just got to think about it.

[Yellow Evan]

Someone commented about the WPAC being unusually quiet in spite of the El Nino (but I couldn't find the post anymore).

I did some research on this (which I already posted on the 2019 WPAC Season thread) and I listed those years with consecutive mild El Nino events since 1965: 1968-1969, 1976-1977, and 1986-1987. In those pairs, the second year with weak El Nino had less active WPAC season than the year preceding it. In fact, 1969 and 1977 are among the least active WPAC seasons since record-keeping began.

Given that 2019 is shaping up to be a continuation of last year's weak El Nino, there could be a possibility that the WPAC season this year will be less active than 2018, if not a below average season in general.

Very interesting, thanks for sharing. Is it the same for the EPAC?

Some quick research:
1968 was more active than 1969 in the EPAC, but I'm not fully trusting of those stats that far back for this basin, but we'll assume that the data is decently reliable and say yes, 1969 was less active than the year before.

1976: 15/9/5
1977: 8/4/0

So 1977 was quite a bit less active than '76.

1986: 17/9/3
1987: 20/10/4

1987 ended up being more active than '86, so this doesn't hold true for all those pairs.

It'll be interesting to see how the WPAC and the EPAC end up this year.

Worth noting that 1987 was a stronger 2nd year Nino than 1969 and 1977 IIRC.

[Kingarabian]

Daily soi is neg again

12z Euro run today shows daily SOI contributions fluctuating between weakly negative/positive for the next couple of days, before tanking the SOI considerably from June 17/18.

The Euro's SOI forecast has verified the past week. Todays 12z Euro run shows that for the next 9 days the daily SOI values will be pretty negative.

[NotSparta]

Daily soi is neg again

12z Euro run today shows daily SOI contributions fluctuating between weakly negative/positive for the next couple of days, before tanking the SOI considerably from June 17/18.

The Euro's SOI forecast has verified the past week. Todays 12z Euro run shows that for the next 9 days the daily SOI values will be pretty negative.

Weird pattern. -SOI, yet no WWB. Just like how there's the strong rising air near the dateline region, but most of that is due to strong easterlies in the east meeting modestly weak trades to the west

[Kingarabian]

Daily soi is neg again

12z Euro run today shows daily SOI contributions fluctuating between weakly negative/positive for the next couple of days, before tanking the SOI considerably from June 17/18.

The Euro's SOI forecast has verified the past week. Todays 12z Euro run shows that for the next 9 days the daily SOI values will be pretty negative.

Weird pattern. -SOI, yet no WWB. Just like how there's the strong rising air near the dateline region, but most of that is due to strong easterlies in the east meeting modestly weak trades to the west

Yeah very strange. Especially considering how strong the suppressed phase of the MJO over the Pacific has been and the amount of sinking motion that was present. Maybe we get a delayed WWB? Currently the GFS850mb wind forecast shows relaxed trades west of the dateline and east of 120W.

I could be wrong but I don't think you get this returning rising air branch simply by having east winds meet west winds. Sure you get a ton of convergence that helps strong convection develop/TC's spin up. I think rising air is reflected off wherever SST's are the warmest, which happens to be near the dateline, and pretty much why the CPAC/EPAC have so much rising air during an El Nino and very little of it during a La Nina. And of course we see an increase of rising air due to MJO and CCKW activity, but it's usually transient as we see the -VP200 anomalies leave the IO.

[Kingarabian]

I think the Euro has some issues with its MJO forecast, showing considerable differences between it and the GFS and CFS. It has had to correct to the latter's solutions.



But still different vs the GFS, CFS, and even the ECMM which uses a different climo period:

[NotSparta]

[/b]

The Euro's SOI forecast has verified the past week. Todays 12z Euro run shows that for the next 9 days the daily SOI values will be pretty negative.

Weird pattern. -SOI, yet no WWB. Just like how there's the strong rising air near the dateline region, but most of that is due to strong easterlies in the east meeting modestly weak trades to the west

Yeah very strange. Especially considering how strong the suppressed phase of the MJO over the Pacific has been and the amount of sinking motion that was present. Maybe we get a delayed WWB? Currently the GFS850mb wind forecast shows relaxed trades west of the dateline and east of 120W.

I could be wrong but I don't think you get this returning rising air branch simply by having east winds meet west winds. Sure you get a ton of convergence that helps strong convection develop/TC's spin up. I think rising air is reflected off wherever SST's are the warmest, which happens to be near the dateline, and pretty much why the CPAC/EPAC have so much rising air during an El Nino and very little of it during a La Nina. And of course we see an increase of rising air due to MJO and CCKW activity, but it's usually transient as we see the -VP200 anomalies leave the IO.

I thought the suppressed MJO had already left the Pacific?

Yes, but the east wind meeting west meaning llvl convergence, which leads to the rising air. Also, that is true, but only thru the SSTAs changing the wind pattern to favor rising/sinking air.

[Kingarabian]

Weird pattern. -SOI, yet no WWB. Just like how there's the strong rising air near the dateline region, but most of that is due to strong easterlies in the east meeting modestly weak trades to the west

Yeah very strange. Especially considering how strong the suppressed phase of the MJO over the Pacific has been and the amount of sinking motion that was present. Maybe we get a delayed WWB? Currently the GFS850mb wind forecast shows relaxed trades west of the dateline and east of 120W.

I could be wrong but I don't think you get this returning rising air branch simply by having east winds meet west winds. Sure you get a ton of convergence that helps strong convection develop/TC's spin up. I think rising air is reflected off wherever SST's are the warmest, which happens to be near the dateline, and pretty much why the CPAC/EPAC have so much rising air during an El Nino and very little of it during a La Nina. And of course we see an increase of rising air due to MJO and CCKW activity, but it's usually transient as we see the -VP200 anomalies leave the IO.

I thought the suppressed MJO had already left the Pacific?

Yes, but the east wind meeting west meaning llvl convergence, which leads to the rising air. Also, that is true, but only thru the SSTAs changing the wind pattern to favor rising/sinking air.

Simply looking at the CHI200 on the GFS and Euro, the models still show sinking motion left over the EPAC. But in regards to the SOI, the SOI technically lags a bit and the positive daily's should've been much more and prolonged with the MJO now over the MC.

[NotSparta]

Yeah very strange. Especially considering how strong the suppressed phase of the MJO over the Pacific has been and the amount of sinking motion that was present. Maybe we get a delayed WWB? Currently the GFS850mb wind forecast shows relaxed trades west of the dateline and east of 120W.

I could be wrong but I don't think you get this returning rising air branch simply by having east winds meet west winds. Sure you get a ton of convergence that helps strong convection develop/TC's spin up. I think rising air is reflected off wherever SST's are the warmest, which happens to be near the dateline, and pretty much why the CPAC/EPAC have so much rising air during an El Nino and very little of it during a La Nina. And of course we see an increase of rising air due to MJO and CCKW activity, but it's usually transient as we see the -VP200 anomalies leave the IO.

I thought the suppressed MJO had already left the Pacific?

Yes, but the east wind meeting west meaning llvl convergence, which leads to the rising air. Also, that is true, but only thru the SSTAs changing the wind pattern to favor rising/sinking air.

Simply looking at the CHI200 on the GFS and Euro, the models still show sinking motion left over the EPAC. But in regards to the SOI, the SOI technically lags a bit and the positive daily's should've been much more and prolonged with the MJO now over the MC.

Yeah SOI is really noisy so it might not reflect what you think it will

[Ntxw]

I thought the suppressed MJO had already left the Pacific?

Yes, but the east wind meeting west meaning llvl convergence, which leads to the rising air. Also, that is true, but only thru the SSTAs changing the wind pattern to favor rising/sinking air.

Simply looking at the CHI200 on the GFS and Euro, the models still show sinking motion left over the EPAC. But in regards to the SOI, the SOI technically lags a bit and the positive daily's should've been much more and prolonged with the MJO now over the MC.

Yeah SOI is really noisy so it might not reflect what you think it will

While it is true the SOI is noisy, especially the daily, it can give you some hints if taken in context over longer periods and trends. It's not useless per say. If the negatives continue to weigh heavily against positives (when forecast says otherwise) there is a disconnect which means one should re-evaluate if the totality of the atmosphere is cooperating with the surface winds and/or SSTA. About 1-2 months ago many were ready to write off the Nino, but the long term SOI told us to hold up and hold steady.