El Nino is Dead. Long Live La Nina.

[snow_wizard]

Niño 3.4 has crashed from +1.2C to +0.4C over the last 5 days.

 

As impressive as that is, the strongest trade winds still don't arrive for several days. The next 10 days all look to feature above average trades, with the strongest winds starting Wednesday.

 

 

This thing is really coming on strong.  Not terribly surprising, I guess, when you look at the subsurface profile.  Nice too see things finally lining up for us to experience cooler temperatures than the past couple of years.

[snow_wizard]

Looks like AAM remains high despite the forcing transition currently underway. We should see the AAM integral go negative sometime within the next 8 weeks, probably in late-June, at which point any semblance of El Niño will be gone.

 

Too bad the site that used to track daily AAM values isn't being updated any longer.  The scientist that did it retired and they didn't bother to find someone else to do it.

[Phil]

This thing is really coming on strong. Not terribly surprising, I guess, when you look at the subsurface profile. Nice too see things finally lining up for us to experience cooler temperatures than the past couple of years.

Like a rubber band, the harder you pull it, the harder it'll snap back. The system's ultimate goal is to maintain equilibrium, so it's no surprise that strong/super Niños are almost always followed by strong and/or extended Niña responses.

[Phil]

Too bad the site that used to track daily AAM values isn't being updated any longer. The scientist that did it retired and they didn't bother to find someone else to do it.

Try this site, I like it more than I did NOAA/CPC:

 

http://www.atmos.albany.edu/student/nschiral/gwo.html

 

Keep in mind, the GFS/GEFS has a low-AAM bias in the extended range.

[Geos]

Yeah el Niño has pretty much had it now. I agree that sometime in June there will be no sign of el Niño anymore.

 

 

 

[Phil]

Niño3.4 is now down to +0.3C. Trade wind burst is just beginning, and is forecast to strengthen over the next week. Starting to think negative anomalies occur before the end of the month, which is quite surprising, considering the Niño 3.4 anomaly was +1.3C one week ago:

 

Here's the trade wind burst forecasted over the next week+:

 

http://www.atmos.albany.edu/student/ventrice/real_time/timeLon/u.anom.30.5S-5N.gif

[snow_wizard]

Pretty impressive to watch the atmosphere and ENSO SST's changing so quickly over the past couple of weeks.  The 30 day SOI will probably be positive within the next 10 days for the first time in ages.  The tropical Pacific OLR anoms have gone neutral and will almost certainly go strongly positive over the next week or two.  As Phil has mentioned the trade winds are about to go nuts.  Little wonder the observed weather has changed so much in the PNW.  I had the big change in our weather pegged for sometime in the Jul to Sep time frame.  Looks like I my have missed on that.

[TT-SEA]

Pretty impressive to watch the atmosphere and ENSO SST's changing so quickly over the past couple of weeks.  The 30 day SOI will probably be positive within the next 10 days for the first time in ages.  The tropical Pacific OLR anoms have gone neutral and will almost certainly go strongly positive over the next week or two.  As Phil has mentioned the trade winds are about to go nuts.  Little wonder the observed weather has changed so much in the PNW.  I had the big change in our weather pegged for sometime in the Jul to Sep time frame.  Looks like I my have missed on that.

 

 

This is an absolutely silly post that I would be mocked for making.

 

The beginning of changes in the ENSO region have nothing to do with this troughy interlude.    There is a well-defined lag that will take until August or September.   

 

This troughy period is very common in late May and early June regardless of the ENSO situation.       

[TT-SEA]

For reference... we had basically the same pattern late May and early June of last year after a warm start.   And that was in the opposite ENSO situation.

 

http://s32.postimg.org/l2q891out/compday_L3_Prk8_OPn_S.gif

 

 

http://s32.postimg.org/pfl3gh639/compday_OQVLHr_MF24.gif

[Phil]

This is an absolutely silly post that I would be mocked for making.

 

The beginning of changes in the ENSO region have nothing to do with this troughy interlude. There is a well-defined lag that will take until August or September.

 

This troughy period is very common in late May and early June regardless of the ENSO situation.

I agree somewhat here. Technically, the IO/MT forcing is responsible for the troughing and the trade wind surge/+SOI/ENSO decline. However, IO/MT forcing is the backbone of La Niña, so it's not exactly separable except by frequency.

 

You're correct that it takes time for the background forcing to stabilize into it's Nińa (IO/MT) mode, and it takes the AAM integral even longer.

 

This IO/MT forcing is intraseasonal (unstable/propagatory) by nature, however, it does mark the beginning of the low frequency forcing transition into La Niña mode. That will probably occur in mid/late July.

[Deweydog]

In general around here ninos tend to be denied their due as they pertain to pattern influence to the point of needing to hit people between the eyes with a 2x4. The inverse tends to apply with ninas.

[snow_wizard]

In general around here ninos tend to be denied their due as they pertain to pattern influence to the point of needing to hit people between the eyes with a 2x4. The inverse tends to apply with ninas.

 

Not true with very strong Nino like this was.  Most of us knew it was going to be painful for cold weather fans.  The fact the torching began so early in the Nino cycle really made this one awful.  Pretty much the 1939 - 1941 Nino was the only one really comparable in that regard.

[Bryant]

This is an absolutely silly post that I would be mocked for making.

 

The beginning of changes in the ENSO region have nothing to do with this troughy interlude. There is a well-defined lag that will take until August or September.

 

This troughy period is very common in late May and early June regardless of the ENSO situation.

The change of tropical forcing shifting into the IO/MT often results in a downstream trough over the west due to latent heat release from convection, which alters the jet stream. The subsequent surface cyclogenesis at the left exit region of the jet streak creates rising heights over the pacific, hence the trough over the west.

 

The shifting of tropical forcing also promotes strengthening easterly winds over the ENSO regions, due to the shift in the Walker Cell. The change of low level winds help to drive the cooler water to the surface.

 

So, how "silly" was his post?

[Bryant]

For reference... we had basically the same pattern late May and early June of last year after a warm start. And that was in the opposite ENSO situation.

 

Not sure what you're trying to prove by cherry picking 2 whole days out of a single month. Trying to prove Jim wrong is going to result in you looking foolish

[Phil]

The change of tropical forcing shifting into the IO/MT often results in a downstream trough over the west due to latent heat release from convection, which alters the jet stream. The subsequent surface cyclogenesis at the left exit region of the jet streak creates rising heights over the pacific, hence the trough over the west.

 

The shifting of tropical forcing also promotes strengthening easterly winds over the ENSO regions, due to the shift in the Walker Cell. The change of low level winds help to drive the cooler water to the surface.

 

So, how "silly" was his post?

Agreed. The reason for the pattern change is very straightforward, and gives credence to the idea of a cooling trend over the PNW through the summer, overall, relative to average.

[TT-SEA]

Not sure what you're trying to prove by cherry picking 2 whole days out of a single month. Trying to prove Jim wrong is going to result in you looking foolish

 

Cherry picking?

 

We had the same pattern during the last week of May and the first part of June last year.     

 

No need to try and prove anything... he statement was not correct.   And if I made that statement the other way it would have been jumped on as being false and misguided.    A trough for a couple weeks in May is not caused by the beginning of a Nina in the tropics.   It happens every year.    It happened last year with a developing Nino as well.     And a neutral period the year before.   It always happens. 

[Jesse]

Cherry picking?

 

We had the same pattern during the last week of May and the first part of June last year.

 

No need to try and prove anything... he statement was not correct. And if I made that statement the other way it would have been jumped on as being false and misguided. A trough for a couple weeks in May is not caused by the beginning of a Nina in the tropics. It happens every year. It happened last year with a developing Nino as well. And a neutral period the year before. It always happens.

If it happens every year, then why are you patting yourself on the back so hard for "predicting" it?

 

Can't have it both ways.

[TT-SEA]

If it happens every year, then why are you patting yourself on the back so hard for "predicting" it?

Can't have it both ways.

Timing.

[Jesse]

Timing.

You gave a month long window during what is essentially the heart of the ULL season, and you never really seemed too picky about when it happened in that window. I think you have flip flopped on early June three times today, for instance. Which is bad because there are only two Canadian runs a day.

[TT-SEA]

You gave a month long window during what is essentially the heart of the ULL season, and you never really seemed too picky about when it happened in that window. I think you have flip flopped on early June three times today, for instance. Which is bad because there are only two Canadian runs a day.

It was way above normal and dry from mid-March through mid-May. Exceptionally warm and dry. Flipped to cooler and wetter right on schedule in the middle of May. This looks to continue for another 10 days or longer. I don't need to debate whether it was a good call. It's always obvious in hindsight. Let's see how summer plays out. I could be exactly right and you will say it was obvious. Whatever.

[Phil]

Cherry picking?

 

We had the same pattern during the last week of May and the first part of June last year.

 

I decided to investigate this more closely. The data below does not appear to support your claim.

 

Here are 500mb geopotential heights and surface temperatures between 5/25/15 and 6/5/15. There's no troughing/ULL present. In fact, quite the opposite look if anything.

 

 

It appears your problem is pattern recognition itself. Or, in other words, your perception of large scale reality is skewed by what you experience firsthand, and is in no way representative of the pattern.

[TT-SEA]

I decided to investigate this more closely. The data below does not appear to support your claim.

 

Here are 500mb geopotential heights and surface temperatures between 5/25/15 and 6/5/15. There's no troughing/ULL present. In fact, quite the opposite look if anything.

 

image.gifimage.gif

 

It appears your problem is pattern recognition itself. Or, in other words, your perception of large scale reality is skewed by what you experience firsthand, and is in no way representative of the pattern.

 

 

Fair enough.

 

It drizzled the entire Memorial Day weekend and June started with 2 days straight of heavy rain here.    Sure did not feel like a ridge... and sure was much cooler and wetter than it had been earlier in the spring.

 

So it turns out that this ULL parade is special and Jim is right that the Nina has taken hold.  

[TT-SEA]

I decided to investigate this more closely. The data below does not appear to support your claim.

 

Here are 500mb geopotential heights and surface temperatures between 5/25/15 and 6/5/15. There's no troughing/ULL present. In fact, quite the opposite look if anything.

 

image.gifimage.gif

 

It appears your problem is pattern recognition itself. Or, in other words, your perception of large scale reality is skewed by what you experience firsthand, and is in no way representative of the pattern.

 

 

This is the actual 500mb pattern in early June 2015.   Probably nothing like the upcoming trough.

 

http://s32.postimg.org/pfl3gh639/compday_OQVLHr_MF24.gif

 

Here is the upcoming trough.   

 

http://mag.ncep.noaa.gov/data/gfs/00/gfs_namer_096_500_vort_ht.gif

 

The top image is actually western ridging... and there is little wonder that the bottom image is all Nina.   

[Phil]

Fair enough.

 

It drizzled the entire Memorial Day weekend and June started with 2 days straight of heavy rain here. Sure did not feel like a ridge... and sure was much cooler and wetter than it had been earlier in the spring.

 

So it turns out that this ULL parade is special and Jim is right that there is little wonder that the Nina has taken hold.

I've also made the mistake of assuming the weather specific to my backyard (or my recollection of it) was/is representative of some particular pattern. I always double check, just to make sure I'm not extrapolating my experiences onto something irrelevant.

 

Here's 5/29 to 6/2, same variables:

 

[Phil]

This is the actual 500mb pattern in early June 2015. Probably nothing like the upcoming trough.

 

http://s32.postimg.org/pfl3gh639/compday_OQVLHr_MF24.gif

 

Here is the upcoming trough.

 

http://mag.ncep.noaa.gov/data/gfs/00/gfs_namer_096_500_vort_ht.gif

 

The top image is actually western ridging... and there is little wonder that the bottom image is all Nina.

 

Dude, that's just one day.

 

In no way, shape, or form does that constitute a "pattern". Heck, even my image from 5/25-6/5 barely qualifies. If this isn't cherry picking, I don't know what is.

[TT-SEA]

I checked each day... the Memorial Day gloomfest last year was the result of a small ULL parked to our east.   Probably would not show up in the smoothed 500mb images so that makes sense.

 

The early June rain was a genuine western trough like we have coming up this week.

[Phil]

A coastal low ruined my 4th of July weekend a few years ago. Therefore, the first half of that July was troughy and wet here.

 

Right?

[TT-SEA]

Dude, that's just one day.

 

In no way, shape, or form does that constitute a "pattern". Heck, even my image from 5/25-6/5 barely qualifies. If this isn't cherry picking, I don't know what is.

 

 

I showed 2 days up above.     

 

I know there was significant rain... checked and sure enough there was a period of troughing in early June.     

 

This is really an irrelevant discussion.   There was cooler/wetter weather in late May and early June of 2015 just like what is occurring now.    Last year was a developing Nino and this year is the opposite.

 

Its silly to attribute a troughy period at this time in the PNW to the Nina.    That is all.    

[TT-SEA]

A coastal low ruined my 4th of July weekend a few years ago. Therefore, the first half of that July was troughy and wet here.

 

Right?

 

 

I never said the first half of any month.   I said there was a wetter/cooler period here last year in late May and early June.   Was that also a developing Nina?     

[Phil]

I checked each day... the Memorial Day gloomfest last year was the result of a small ULL parked to our east.   Probably would not show up in the smoothed 500mb images so that makes sense.

 

The early June rain was a genuine western trough like we have coming up this week.

You sure about that? Selective memory?

 

[Phil]

I never said the first half of any month. I said there was a wetter/cooler period here last year in late May and early June. Was that also a developing Nina?

You said "we had the same pattern". Doofus. No, we actually didn't.

 

Three days doesn't constitute a "pattern". Unless you think you can predict the timing of random specific lows two months in advance? I know I certainly can't.

[TT-SEA]

You sure about that? Selective memory?

 

image.gifimage.gif

 

What are you showing me?  

 

Here is each day:

 

 

June 1st  -  (PNW trough)

http://s32.postimg.org/6uunvi9s5/image.gif

 

June 2, 2015  (PNW trough)

 

http://s32.postimg.org/z62w6p6h1/image.gif

 

June 3, 2015  (PNW trough)

 

http://s32.postimg.org/l2q891out/compday_L3_Prk8_OPn_S.gif

 

June 4, 2015   (PNW trough)

 

http://s32.postimg.org/pfl3gh639/compday_OQVLHr_MF24.gif

[TT-SEA]

Again.. the bottom line is not that last year was exactly like this year.   Not the point at all.

 

The point is that is was silly to say there is little wonder that it has turned cooler and wetter this week because of Nina.      That is what Jim said.  

 

Did it turn cooler and wetter late last May and early June because of a Nina?   Because that also happened.

[Phil]

What are you showing me?

 

Here is each day:

 

 

You're reading the data wrong because you're looking at absolute heights, as opposed to height anomalies. There is a climatological, semipermanent NE-PAC trough in the raw height fields (topographic and thermodynamic forcing), so looking at the absolute heights is worthless. In the same manner, there's a climatological, semipermanent lee-trough over central North America.

 

Also, five days doesn't constitute a pattern, either. So, again, your analysis is nonsensical.

[TT-SEA]

You're reading the data wrong because you're looking at raw/absolute heights, as opposed to anomalies. There is a climatological, semipermanent NEPAC trough in the raw height fields (topographic and thermodynamic forcing).

 

Also, five days doesn't constitute a pattern, either. So, again, your analysis is nonsensical.

 

 

OK... let me understand this.    

 

You are saying that those images DO NOT depict a troughy period for us??       Really?   

 

I give up.   I know what a trough looks like... and that is a troughy period here.  

 

That was a troughy period... not a troughy pattern... got it.     I understand that distinction and that is fair.

[BLI snowman]

This infamous "cool" pattern we had last year during late spring proved to be pretty inconsequential IMO.

 

PDX had four out of five days in the 80s at the end of May 2015 and then shot right back into the mid 80s by June 5. The lower heights and cooler weather proved to be transient, at best.

 

Remains to be seen how the next few weeks play out of course but it's really not hard to imagine it being a good deal cooler than what we endured last year around this time.

[Phil]

OK... let me understand this.

 

You are saying that those images DO NOT depict a troughy period for us?? Really?

 

I give up. I know what a trough looks like... and that is a troughy period here.

 

Pattern... period... whatever. That was a troughy period... not a troughy pattern got it.

There's no way you're this stupid.

 

Do you think geopotential heights are perfectly aligned by-latitude across the globe? So, the semipermanent NATL/NPAC highs are just anomalous ridges that should be colored red 24/7?

[TT-SEA]

There's no way you're this stupid. Do you think geopotential heights are perfectly aligned by-latitude across the globe?

 

 

OMG.

 

Is that a trough over the PNW for those 4 days or not???  

 

What is that?  A ridge??   

[TT-SEA]

June 1-4, 2015 featured a significant trough over the PNW,   

 

End of story.

 

You want to argue that the sky is green and I am stupid for not seeing it??   

[Phil]

OMG.

 

Is that a trough over the PNW for those 4 days or not???

 

What is that? A ridge??

This is "climatology" for 6/1-6/5.

 

A permanent trough! All the way down to California! Oh noes!