2014 ENSO Mega Thread

[icebreaker5221]

Thanks for the heads up.

I guess we'll see what ends up happening...I think what recently went through the IO domain was a CCKW, no? The SSTA response was impressive though, more akin to true MJO.

 

Yes, there was enhanced VP in the IO associated with a Kelvin wave overlaid upon the suppressed phase of the MJO, leading to somewhat of a false spike in the RMM index.  However, I would expect the region of suppressed convection currently over the IO to drift eastward with time, not vanish entirely as the GFS suggests. 

[AlaskaETC]

http://www.bom.gov.au/climate/enso/

 

El Niño indicators ease

 

Issued on Tuesday 29 July 2014 | Product Code IDCKGEWW00

Despite the tropical Pacific Ocean being primed for an El Niño during much of the first half of 2014, the atmosphere above has largely failed to respond, and hence the ocean and atmosphere have not reinforced each other. As a result, some cooling has now taken place in the central and eastern tropical Pacific Ocean, with most of the key NINO regions returning to neutral values.

While the chance of an El Niño in 2014 has clearly eased, warmer-than-average waters persist in parts of the tropical Pacific, and the (slight) majority of climate models suggest El Niño remains likely for spring. Hence the establishment of El Niño before year's end cannot be ruled out. If an El Niño were to occur, it is increasingly unlikely to be a strong event.

Given the current observations and the climate model outlooks, the Bureau’s ENSO Tracker has shifted to El Niño WATCH status. This means the chance of El Niño developing in 2014 is approximately 50%, which remains significant at double the normal likelihood of an event.

El Niño is often associated with wide scale below-average rainfall over southern and eastern inland areas of Australia and above-average daytime temperatures over southern Australia. Similar impacts prior to the event becoming fully established regularly occur.

The Indian Ocean Dipole (IOD) index has been below −0.4 °C (the negative IOD threshold) since mid-June, but needs to remain negative into August to be considered an event. Model outlooks suggest this negative IOD is likely to be short lived, and return to neutral by spring. A negative IOD pattern typically brings wetter winter and spring conditions to inland and southern Australia.

 

Hmm...interesting.

[Wannabehippie]

I am cheering on an El Nino in hopes that it eases if not breaks the drought conditions in California.

[griteater]

It looks like we have a weak kelvin wave trying to build.  CFS shows the warm anomalies building through the fall and pushing us into El Nino...it looks overdone, but we'll see.

 

 

 

[loadletterpaper]

Been following this thread on and off. Stumbled on this and thought it'd be of interest.  Unfortunately the Nature CC paper is pay for.

08/05 ars article with Nature ref: http://arstechnica.com/science/2014/08/strong-la-ninas-recently-blame-the-atlantic-and-a-volcano/

[griteater]

August release of the MEI continues with a weak Nino ranking for the Jun/Jul period.  Here's the progression of the MEI rankings over the last 5 bi-monthly periods:

 

Feb/Mar: Neutral

Mar/Apr: Neutral

Apr/May: Moderate Nino

May/Jun: Weak Nino

Jun/Jul: Weak Nino

 

The last 2-3 weeks have featured the most notable westerly wind anomalies that we've seen in 3 months...and new subsurface warming has commenced in the central Pacific.  On the flip side, it looks like easterly wind anomalies are set to return during the mid-late August period as we go into a period of low AAM / inactive phase of the MJO

[JBG]

Do the two storms heading for Hawaii indicate that something may be happening?

[uncle W]

Do the two storms heading for Hawaii indicate that something may be happening?

something is always happening...

http://en.wikipedia.org/wiki/List_of_Hawaii_hurricanes

[Kory]

Do the two storms heading for Hawaii indicate that something may be happening?

It may help bring westerly winds to the equator which in turn will help the building EKW.  

[Ginx snewx]

It may help bring westerly winds to the equator which in turn will help the building EKW.  

Or not, there are much larger forces at work

http://earth.nullschool.net/#current/wind/isobaric/1000hPa/orthographic=-147.10,-13.06,380

[Sunny and Warm]

I recall in the past reading that ENSO has a 2-3 month lagging effect on USA weather.  If that is true, and if we look at where ENSO may be for the next 3 months, we may have no more than a weak Nino effect through winter, regardless of whether it grows stronger at a later point or not.

[GaWx]

I recall in the past reading that ENSO has a 2-3 month lagging effect on USA weather.  If that is true, and if we look at where ENSO may be for the next 3 months, we may have no more than a weak Nino effect through winter, regardless of whether it grows stronger at a later point or not.

 

 Based on my own research, I really don't know whether or not this is consistently true (tough call if there is a lag from, say, Nino 3.4 SST's on a consistent basis) though you may be right. If there is a lag, I think it is longer from the SOI since there appears to be some lag in some years from spring SOI to SST's per my own research. Regardless, chances are increasing that the fall-winter peak will be weak. If it ends up peaking as weak, that opens the door to a very good shot at a cold E US winter if the PDO can remain positive and we get a -NAO averaged over DJF. The combo of weak Nino, +PDO, and -NAO is about the best combo for the best shot at a really cold E US winter.

Some of the coldest E US winters have been when there was a weak Nino/+PDO/-NAO including 1977-8, 1976-7, 1969-70, 1939-40, 1904-5, & 1900-1. OTOH 2006-7, 2004-5, 1953-4, and 1951-2 had +NAO averaged DJF's. 1953-4 and 1951-2 had a -PDO.

 

[It's Always Sunny]

I recall in the past reading that ENSO has a 2-3 month lagging effect on USA weather.  If that is true, and if we look at where ENSO may be for the next 3 months, we may have no more than a weak Nino effect through winter, regardless of whether it grows stronger at a later point or not.

I think a 2-3 month lag period is awfully long, considering the atmosphere is Lagrangian in nature. I think that idea lacks a lot of research considering there are so many factors other than ENSO that can impact U.S. weather in any given season. Can ENSO impact us in some sort of way, yes, because it's been proven but as far as a lag I am unsure of. I never heard anyone in my field say it's due to a "lag effect". This is just my two cents not saying that any of my ideas are correct but it's where my line of thinking is. 

[It's Always Sunny]

 Based on my own research, I really don't know whether or not this is consistently true (tough call if there is a lag from, say, Nino 3.4 SST's on a consistent basis) though you may be right. If there is a lag, I think it is longer from the SOI since there appears to be some lag in some years from spring SOI to SST's per my own research. Regardless, chances are increasing that the fall-winter peak will be weak. If it ends up peaking as weak, that opens the door to a very good shot at a cold E US winter if the PDO can remain positive and we get a -NAO averaged over DJF. The combo of weak Nino, +PDO, and -NAO is about the best combo for the best shot at a really cold E US winter.

Some of the coldest E US winters have been when there was a weak Nino/+PDO/-NAO including 1977-8, 1976-7, 1969-70, 1939-40, 1904-5, & 1900-1. OTOH 2006-7, 2004-5, 1953-4, and 1951-2 had +NAO averaged DJF's. 1953-4 and 1951-2 had a -PDO.

 

WeakNino+PDO-NAO.png

Your research makes sense considering those teleconnections in correlation pave way for a good set up for a cold NE winter.

[griteater]

Definitely seeing some level of warming in the upper subsurface

 

 

 

Also, the biased corrected CFS wants to continue with westerly wind anomalies across the central and eastern equatorial Pacific in the upcoming weeks despite us moving into a -AAM / suppressed MJO phase.

 

[WEATHER53]

Cosgrove wrote Nino is alive and well. His newletter is still stellar, too bad trogs. ran him off of here.

[Sunny and Warm]

Cosgrove wrote Nino is alive and well. His newletter is still stellar, too bad trogs. ran him off of here.

I like Larry, but his ego is much larger than his skill set.  Nino may come at some point, but it is not alive and well.  Nino is in a dogfight and the extent to which it survives is not apparent at this time.  He ran himself off Eastern years ago.  I don't actually remember him here.

[GaWx]

Cosgrove wrote Nino is alive and well. His newletter is still stellar, too bad trogs. ran him off of here.

I agree that he writes an absolutely stellar newsletter. However, have you noticed how many gigabytes it takes up now in its multiple parts? I think it is close to 20. The newsletter from a year or so ago was generally under 5 or so when it was in one part if I recall correctly. I think it might be best if he were to take out some of the graphics to reduce the GB's as I'd think some email systems have limits in how much can be stored at one time. Regardless, I assume he broke it into parts because many systems would reject a single 20 GB email. I may email him about this. Your opinion about the size?

[GaWx]

I like Larry, but his ego is much larger than his skill set. Nino may come at some point, but it is not alive and well. Nino is in a dogfight and the extent to which it survives is not apparent at this time. He ran himself off Eastern years ago. I don't actually remember him here.

This struggling/dogfight may very well cause the Niño peak to be weak and west-based vs. the strong to super basin wide Niño that some models had suggested early in the year. If this turns out to be the case, the result in the E US could, ironically enough, very well turn out to be much more impactful than would have otherwise been the case due to much colder temperatures and possibly also heavier snowfall. 2009-10 was the rare very cold strong Niño to produce the coldest winter since 1977-8 and top ten cold winter at Atlanta and much of the SE in addition to well above normal snowfall in Atlanta and many areas. I'm sure that some people think that "weak" Niño will likely result in a boring winter. The facts (history) refute that at least in terms of strong cold potential (see 1977-8, 1976-7, 1969-70, 1939-40, 1904-5, and 1885-6) and in way above normal wintry precip. in some cases (2004-5/1969-70 in good deal of the NE, 1977-8 though not in ATL, the frigid 1976-7 giving Savannah an extremely rare two measurable snowfalls and flurries to Miami Beach/Nassau, 1939-40 producing both a 10" snow & a major ZR during the coldest month on record at ATL, 1904-5 producing series of major ZR at ATL). Regardless, it would still be vital that the +PDO continues and we get a -NAO in winter to give the E US a good shot at a quite cold winter even if we end up with a weak Niño peak this fall/winter.

[WEATHER53]

I like Larry, but his ego is much larger than his skill set.  Nino may come at some point, but it is not alive and well.  Nino is in a dogfight and the extent to which it survives is not apparent at this time.  He ran himself off Eastern years ago.  I don't actually remember him here.

That's mostly baloney. Larry was a solid contributor but the miscreats liked tweaking him and he tired of it. You are a fine man but as far as "skill set" Larry contributed way more than yourself. There is Nothing to indicate nino will be less than a 1-1.5, it is in fact alive and well.

[Harry]

That's mostly baloney. Larry was a solid contributor but the miscreats liked tweaking him and he tired of it. You are a fine man but as far as "skill set" Larry contributed way more than yourself. There is Nothing to indicate nino will be less than a 1-1.5, it is in fact alive and well.

 

 

The SST's ( how nino is measured ) tell another story.

 

 

Still have a ways to go before it is even declared. My early guess ( using historical events ) I would go with a range of +0.7 to +1.1 for tri monthly max. Last reading was +0.1!

[uncle W]

I'm looking at el nino's that came after at least three years of la nina or neutral...checking the mei I came up with these analogs...The last four winters had at least  a negative -0.6 oni for DJF period...bottom five analogs were the weakest...

[GaWx]

 Fwiw, the brand new Euro weeklies suggest a warming in Nino 3.4 from ~0 to +0.1 C anomaly this week to near the low end of weak Nino (say ~+0.5 C to +0.6 C) during the first week of Sep. At the same time, they show a weakening of the Nino 1+2 warmth (i.e., they're showing a transition from east based toward neutral based for the warmth). Also, they show the +PDO holding pretty firm. These weeklies have been pretty consistent.

 IMO, if it were to verify (looking ahead toward winter), this would be a good trend for cold potential as it shows a trend toward at least a weak Nino by autumn along with the continued +PDO.

[Quixotic1]

Looking at the subsurface temps moving east with the KW, that seems very reasonable.

[Kory]

 Fwiw, the brand new Euro weeklies suggest a warming in Nino 3.4 from ~0 to +0.1 C anomaly this week to near the low end of weak Nino (say ~+0.5 C to +0.6 C) during the first week of Sep. At the same time, they show a weakening of the Nino 1+2 warmth (i.e., they're showing a transition from east based toward neutral based fro the warmth). Also, they show the +PDO holding pretty firm. These weeklies have been pretty consistent.

 IMO, if it were to verify (looking ahead toward winter), this would be a good trend for cold potential as it shows a trend toward at least a weak Nino by autumn along with the continued +PDO.

Interesting note regarding the PDO, it's still positive, but it's showing a downward trend.  It peaked in May, then sharply dropped by June and continues to fall into July.  I could definitely see a neutral PDO by winter.

 

2014** 0.30 0.38 0.97 1.13 1.80 0.82 0.70

 

http://jisao.washington.edu/pdo/PDO.latest

[GaWx]

Interesting note regarding the PDO, it's still positive, but it's showing a downward trend.  It peaked in May, then sharply dropped by June and continues to fall into July.  I could definitely see a neutral PDO by winter.

 

2014** 0.30 0.38 0.97 1.13 1.80 0.82 0.70

 

http://jisao.washington.edu/pdo/PDO.latest

 

 Based on the jisao PDO table's historical stats: when considering the combo of the still persistent +PDO pattern so far this year as well as the July PDO of a still pretty solidly positive +0.70 (that is at the 73 percentile for July), I'm currently giving it about an 80% chance for a +PDO this coming DJF averaged on the jisao table. Out of the 114 winters listed, 60 (52%) of them had a +PDO..so ~50%. So, this 80% chance is well above the long-term based chance.

 

Edit: A key for a +PDO to continue would be to maintain the below normal SST's (blues) centered near 40N along the dateline. That along with the warmth in the E Pacific is the textbook +PDO for those who don't know.

[AlaskaETC]

I've seen some discussion recently on the latest SST signatures...some belief about the cooler waters near Australia linking up indicating SOI is active. Something to pay attention to?

[GaWx]

I've seen some discussion recently on the latest SST signatures...some belief about the cooler waters near Australia linking up indicating SOI is active. Something to pay attention to?

Regarding the SOI, we're currently within a pretty long -SOI string, which looks to continue for a few more days (tomorrow's should be a stronger negative thanks to sharply higher Darwin pressure). In about 3-4 days, we might squeeze in 1-2 positives. However, even if so, negatives should return right away for at least a few days after that per the 0Z Euro.

Overall, Darwin's pressures have been mainly near to above average, which is consistent with El Niño. However, Tahiti's pressures haven't really been low in general, which would also be consistent with El Niño. They've been more like near average overall from what I've seen. Be that as it may, moderate negatives have finally taken over at least for now, which is somewhat conducive/associative with some warming in Niño 3.4 fwiw.

[AlaskaETC]

Regarding the SOI, we're currently within a pretty long -SOI string, which looks to continue for a few more days (tomorrow's should be a stronger negative thanks to sharply higher Darwin pressure). In about 3-4 days, we might squeeze in 1-2 positives. However, even if so, negatives should return right away for at least a few days after that per the 0Z Euro.

Overall, Darwin's pressures have been mainly near to above average, which is consistent with El Niño. However, Tahiti's pressures haven't really been low in general, which would also be consistent with El Niño. Be that as it may, moderate negatives have finally taken over at least for now, which is somewhat conducive/associative with some warming in Niño 3.4 fwiw.

 

Thanks for the feedback, that makes sense.

[Ji]

is the postive PDO more important for us than the Nino becoming moderate. I would think a Positive PDO and even a weak Nino would give us some nice weather this winter