Why the Stratosphere Gave a False ENSO Signal in the Spring

[Jaguars]

The latest CFS agrees with me

what did past winter's nina peak at?

[HM]

My take is that we are near the warming peak, and the warming eq stratosphere, the declining OHC and the -PDO will eventually drive the ENSO very close to Niña territory (and I'm not touching the sun for now). Clearly, the ENSO models have hinted at a slight dip trend around mid/late summer, but I think it might be a bit sooner and probably stronger... what's your take on this HM?

Sorry, Jorge, I missed this man. Yes, I am firmly in the no El Nino camp.

After the FW disturbance, the 50mb layer has tried to make a +QBO comeback, aiding in subtropical cooling. This has been an agent of slowing the polar warming process and prolonging the -AO regime. However, in recent days, it has begun to take somewhat of a hit. We'll see how this goes but it is likely to time well with the seasonal cycle and typical ENSO climo...in other words...a dampened signal by that point.

Here is the 50mb link showing the recovering toward +QBO-like state:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/50mb2525.gif

[HM]

Disagree. The start of the season could certainly be active, but I think we'll see an early end (very much in contrary to 2005), as QBO easterlies descend, imposing warm stratospheric temperature anomalies off the equator.

I'm sticking with the numbers I posted in February: 14/8/5, with 12 storms between June-September

I would think again about these ideas and I disagree with your early end (although I'm not sure what you mean by that...at what time do we quit?) and your seasonal total. Years like 2008, 2001 and 2000 are some examples of ENSO trends in the modern +AMO period right? Well this year's TNA is slaughtering those years to death and all of them had 15 (2008 had 16 but that's including miserable Arthur). Are you suggesting the QBO will be the reason we don't make 15?

[OKpowdah]

I would think again about these ideas and I disagree with your early end (although I'm not sure what you mean by that...at what time do we quit?) and your seasonal total. Years like 2008, 2001 and 2000 are some examples of ENSO trends in the modern +AMO period right? Well this year's TNA is slaughtering those years to death and all of them had 15 (2008 had 16 but that's including miserable Arthur). Are you suggesting the QBO will be the reason we don't make 15?

By early end, I mean an active August and September, coming to a halt in October, with climatology or less for the rest of the year. I guess early *end* isn't the best way to put it. And yeah, the QBO is a big factor in limiting this season's productivity (IMO). I'm not sure what's magic about the number 15 ... my forecast is for 14; do I lose if we get 15 storms?

2001 and 2008 both had opposite stratosphere wind anomalies than we have now. 2000 is a decent analog, and I think it had 14 storms that year unless I missed one. But yeah, for the stratosphere and Pacific, 2000 looks good to me. It had a very active August and September, and then ended with 3/1/0 in October ... nothing after October 22nd.

It's worth noting that 2000,1,and 8 all held onto La Nina characteristics a little better than we are right now. AAM anomalies were notably lower in those three years. 2000 was in the middle of a three year La Nina, which is one point against it. We are not heading for a second La Nina winter. Neutral is likely; maybe even warm neutral IMO. That would be another negative factor to the Atlantic tropical season, again weighted towards the end.

That's just what my train of thought is right now. I'll include the same disclaimer as in the New England winter thread, that I haven't really delved into the general circulation much in the last year. I'm hoping to find some time and motivation this summer to get back into it.

[OKpowdah]

By the way, combining MJO wave timing with the QBO shift last year nailed the time distribution of Atlantic tropical activity.

I posted a forecast in May, based on the QBO shift, calling for a slow start followed by 9/6/4 for the 8/20-9/30 period ... and we got 11/6/4. This says nothing anything about my forecasting ability ... for every one good forecast, I have 10 busts lol. I'm just showing an example of where I think the QBO played a major role.

[phil882]

2001 and 2008 both had opposite stratosphere wind anomalies than we have now. 2000 is a decent analog, and I think it had 14 storms that year unless I missed one. But yeah, for the stratosphere and Pacific, 2000 looks good to me. It had a very active August and September, and then ended with 3/1/0 in October ... nothing after October 22nd.

It's worth noting that 2000,1,and 8 all held onto La Nina characteristics a little better than we are right now. AAM anomalies were notably lower in those three years. 2000 was in the middle of a three year La Nina, which is one point against it. We are not heading for a second La Nina winter. Neutral is likely; maybe even warm neutral IMO. That would be another negative factor to the Atlantic tropical season, again weighted towards the end.

First point... aren't the 2000 October numbers actually above average for an October? I got 2.1/1.1 according to 1981-2010 average values for tropical storms and hurricanes in October.

Second point... Are you sure about that, since the CFS is becoming more adamant about a recurring La Nina in the second half of this year.

[OKpowdah]

First point... aren't the 2000 October numbers actually above average for an October? I got 2.1/1.1 according to 1981-2010 average values for tropical storms and hurricanes in October.

Second point... Are you sure about that, since the CFS is becoming more adamant about a recurring La Nina in the second half of this year.

1) Not sure what the exact numbers are, but I think 3/1/0 would be around normal for 1995-present Octobers, and certainly below normal for Oct-Nov-Dec

2) Yeah, CFS projections would make me cautious about going warmer than 0, but I do not think we'll see a second La Nina.

[MN Transplant]

A compilation of the models.

[wxmx]

A compilation of the models.

The latest and greatest from the Euro ... close to 0, slightly cold neutral by Dec, just a hair below the May forecast.

[HM]

By early end, I mean an active August and September, coming to a halt in October, with climatology or less for the rest of the year. I guess early *end* isn't the best way to put it. And yeah, the QBO is a big factor in limiting this season's productivity (IMO). I'm not sure what's magic about the number 15 ... my forecast is for 14; do I lose if we get 15 storms?

2001 and 2008 both had opposite stratosphere wind anomalies than we have now. 2000 is a decent analog, and I think it had 14 storms that year unless I missed one. But yeah, for the stratosphere and Pacific, 2000 looks good to me. It had a very active August and September, and then ended with 3/1/0 in October ... nothing after October 22nd.

It's worth noting that 2000,1,and 8 all held onto La Nina characteristics a little better than we are right now. AAM anomalies were notably lower in those three years. 2000 was in the middle of a three year La Nina, which is one point against it. We are not heading for a second La Nina winter. Neutral is likely; maybe even warm neutral IMO. That would be another negative factor to the Atlantic tropical season, again weighted towards the end.

That's just what my train of thought is right now. I'll include the same disclaimer as in the New England winter thread, that I haven't really delved into the general circulation much in the last year. I'm hoping to find some time and motivation this summer to get back into it.

Sam, sorry for the late response. Yeah, I get what you mean about the early end now (which could happen the way you say). I don't think there is anything special about the number "15" but I used that (the avg of the analogs) as an argument for going over 14 named storms since this year's TNA is higher than 2008/01/00. But now that you mention it, 15 is actually an important number to clients these days because that is the average since 1995 (well 14.8 I believe, but correct me if I'm wrong), when the +AMO started. In the last 10 years, the average has been 15.5. So by forecasting 14, you are saying that it will be slightly below the average of the last 10 years. My argument is: if the TNA is beating out all the years since 2000 that had a similar ENSO trend, why wouldn't we at least reach the 10-year average? So, yeah, I think any "benchmark number" of named storms to use is silly but it is the implications that are important to whomever is reading the forecast/clients etc.

I don't think 2000 had slightly less activity than 2001/2008 because of the QBO (although you may not be implying that--sorry if that's the case). I think that we exhausted the available heat content because it was year 3 of La Niña conditions. Notice the TNA went negative in April and May of 2000 while 2001 and 2008 went positive and were increasing. In the end, I think the QBO has a more indirect effect on the Atlantic tropical season in a +AMO. I think it may help direct where areas of development are more likely and that sort of thing (like 2005). Also, we peaked our +QBO this year around April for 30mb and May for 50mb. In 2000, we were already changing to neutral/negative at 30mb. So, if the QBO does end up affecting totals this year, it may not matter for most of the season. In 2000, the 50mb values were basically neutral in the autumn, getting to a meager -0.50 in Nov and -0.72 in December.

http://www.cpc.ncep.noaa.gov/data/indices/qbo.u50.index

[tacoman25]

CFS has really trended downwards lately. Undoubtedly overdone, but still a bit surprising to see.

[nzucker]

CFS has really trended downwards lately. Undoubtedly overdone, but still a bit surprising to see.

I think many people are underestimating how powerful the resurgence of the Niña could be. I think we could see a weak Niña for Winter 11-12 as many of the warm subsurface waters have been mixed out, although there's probably not enough juice for a real potent Niña like the last one.

[MN Transplant]

CFS has really trended downwards lately. Undoubtedly overdone, but still a bit surprising to see.

Split the difference!

[am19psu]

CFS has really trended downwards lately. Undoubtedly overdone, but still a bit surprising to see.

Split the difference!

Anyone want to post the KMA

Here is the EUROSIP ensemble, which is the most skillful...

[River Card]

Wow all this data and graphs and seemingly the last several years have been nina or nino, strong blocking so in a nut shell what "could" this all mean for winter? I know it's way to soon but the last several winters have been awfully good around the midwest...I just hold my breath for the overdue clunker. Is this that year? Man been ages since it's been neutral.

[nzucker]

Wow all this data and graphs and seemingly the last several years have been nina or nino, strong blocking so in a nut shell what "could" this all mean for winter? I know it's way to soon but the last several winters have been awfully good around the midwest...I just hold my breath for the overdue clunker. Is this that year? Man been ages since it's been neutral.

I would assume a weak Niña is decent for the Midwest, and that seems to be the most likely option along with negative-neutral for this coming winter.

I know 08-09 and 66-67 were solid winters for Chicago, both of which were borderline weak Niñas. Do you remember how you guys did in 00-01 and 60-61, also being considered as analogs?

I don't see too many unfavorable signals this winter...-QBO/solar min tends to promote sudden stratospheric warmings, which help to tank the NAO/AO. A weak Niña usually means plenty of cold air over Canada with an amplified Aleutian ridge and colder global temperatures, especially when it follows a stronger Niña. We saw how winters like 08-09 and 00-01 had a nice pipeline of cold coming in from Western/Central Canada, both weak Niñas preceded by stronger cold ENSO winters. I really like this combination as it gives you the benefits of Niña (more cold/ice cover over the Arctic, more likelihood of the PV being in Canada versus Siberia, potent northern stream with lots of clippers and redevelopers) without the drawbacks of a real strong Niña (potential for a big GoA low, too little southern stream). I also like how the -NAO block has redeployed itself after a fairly long absence save for late March. It's obvious that the consistency of the Greenland block, which started back in Summer 2008, is not fading one bit.

[tacoman25]

Split the difference!

I could be wrong, but I believe the CFS has been more accurate.

[OKpowdah]

Sam, sorry for the late response. Yeah, I get what you mean about the early end now (which could happen the way you say). I don't think there is anything special about the number "15" but I used that (the avg of the analogs) as an argument for going over 14 named storms since this year's TNA is higher than 2008/01/00. But now that you mention it, 15 is actually an important number to clients these days because that is the average since 1995 (well 14.8 I believe, but correct me if I'm wrong), when the +AMO started. In the last 10 years, the average has been 15.5. So by forecasting 14, you are saying that it will be slightly below the average of the last 10 years. My argument is: if the TNA is beating out all the years since 2000 that had a similar ENSO trend, why wouldn't we at least reach the 10-year average? So, yeah, I think any "benchmark number" of named storms to use is silly but it is the implications that are important to whomever is reading the forecast/clients etc.

I don't think 2000 had slightly less activity than 2001/2008 because of the QBO (although you may not be implying that--sorry if that's the case). I think that we exhausted the available heat content because it was year 3 of La Niña conditions. Notice the TNA went negative in April and May of 2000 while 2001 and 2008 went positive and were increasing. In the end, I think the QBO has a more indirect effect on the Atlantic tropical season in a +AMO. I think it may help direct where areas of development are more likely and that sort of thing (like 2005). Also, we peaked our +QBO this year around April for 30mb and May for 50mb. In 2000, we were already changing to neutral/negative at 30mb. So, if the QBO does end up affecting totals this year, it may not matter for most of the season. In 2000, the 50mb values were basically neutral in the autumn, getting to a meager -0.50 in Nov and -0.72 in December.

http://www.cpc.ncep....s/qbo.u50.index

Okay, that's certainly fair, that 15 is an important benchmark. The TNA is definitely a legitimate argument for at least as much activity as the years you referenced. I might say that the TNA would be a greater influence on the maximum intensity of storms, and thus the number of hurricanes and major hurricanes, versus named storms. I wouldn't say the QBO directly dictated the total number of NS in 2000, but it definitely influenced it IMO. Like I said, I think a very similar evolution to the season is possible. Very active early, and a slow Oct-Nov-Dec. 2000 was year 2 of La Nina, not 3, but point taken, and definitely a possible factor in slightly lower numbers.

Yeah the decent of the QBO easterlies has slowed a lot in the last month or so, so we'll see where we are by September. I don't think the QBO directly affects totals, but affects like you said the spatial distribution of storms, and also the temporal distribution, which when superimposed on climatology, has an effect on totals.

We'll see what happens. To make things interesting, I'll stick with my forecast until it's doomed to fail

[wxmx]

POAMA is subpar, IMO. The Eurosip has too much weight on the Ukmet and meteo france models. In my limited experience, the ECMWF with a touch of CFS for recent trends is a good blend.

I went for 16 NS in May, but I think I will fall a bit short, 17 or 18 look like better numbers

[am19psu]

POAMA is subpar, IMO. The Eurosip has too much weight on the Ukmet and meteo france models. In my limited experience, the ECMWF with a touch of CFS for recent trends is a good blend.

Interesting. Given its prowess in forecasting number of TCs, I'd have thought the UKMet GloSea model was a "good" seasonal model as well. I don't have a large sample to base it on, though. I agree that Meteo France is garbage.

[River Card]

I would assume a weak Niña is decent for the Midwest, and that seems to be the most likely option along with negative-neutral for this coming winter.

I know 08-09 and 66-67 were solid winters for Chicago, both of which were borderline weak Niñas. Do you remember how you guys did in 00-01 and 60-61, also being considered as analogs?

I don't see too many unfavorable signals this winter...-QBO/solar min tends to promote sudden stratospheric warmings, which help to tank the NAO/AO. A weak Niña usually means plenty of cold air over Canada with an amplified Aleutian ridge and colder global temperatures, especially when it follows a stronger Niña. We saw how winters like 08-09 and 00-01 had a nice pipeline of cold coming in from Western/Central Canada, both weak Niñas preceded by stronger cold ENSO winters. I really like this combination as it gives you the benefits of Niña (more cold/ice cover over the Arctic, more likelihood of the PV being in Canada versus Siberia, potent northern stream with lots of clippers and redevelopers) without the drawbacks of a real strong Niña (potential for a big GoA low, too little southern stream). I also like how the -NAO block has redeployed itself after a fairly long absence save for late March. It's obvious that the consistency of the Greenland block, which started back in Summer 2008, is not fading one bit.

Thank you Zucker, yeah the weak ninas actually produced some hyper active periods of winter weather here with seemingly clipper after clipper, and although not any huge events, the snow cover and the cold and it's persistence is what really stands out. Seemed like fall would hang on till about Dec 5th and once winter locked in that was it. I'll keep monitoring the board here and see how things look as we progress towards Sept. Thanks again!

[wxmx]

Interesting. Given its prowess in forecasting number of TCs, I'd have thought the UKMet GloSea model was a "good" seasonal model as well. I don't have a large sample to base it on, though. I agree that Meteo France is garbage.

I have no numbers to back my limited empiric knowledge, though.

[wxmx]

I have no numbers to back my limited empiric knowledge, though.

But yeah, Meteo France models should be ousted from the Eurosip. Also POAMA rather sucks... it has a warm bias. CFS is ok, and UKMet is fine.

[Harry]

I would assume a weak Niña is decent for the Midwest, and that seems to be the most likely option along with negative-neutral for this coming winter.

I know 08-09 and 66-67 were solid winters for Chicago, both of which were borderline weak Niñas. Do you remember how you guys did in 00-01 and 60-61, also being considered as analogs?

I don't see too many unfavorable signals this winter...-QBO/solar min tends to promote sudden stratospheric warmings, which help to tank the NAO/AO. A weak Niña usually means plenty of cold air over Canada with an amplified Aleutian ridge and colder global temperatures, especially when it follows a stronger Niña. We saw how winters like 08-09 and 00-01 had a nice pipeline of cold coming in from Western/Central Canada, both weak Niñas preceded by stronger cold ENSO winters. I really like this combination as it gives you the benefits of Niña (more cold/ice cover over the Arctic, more likelihood of the PV being in Canada versus Siberia, potent northern stream with lots of clippers and redevelopers) without the drawbacks of a real strong Niña (potential for a big GoA low, too little southern stream). I also like how the -NAO block has redeployed itself after a fairly long absence save for late March. It's obvious that the consistency of the Greenland block, which started back in Summer 2008, is not fading one bit.

08-09, 66-67, and 00-01 was terrific winters in these parts and all top 5 for snowiest with 08-09 being the snowiest and 66-67 being the 3rd snowiest on record. Unsure of what happened in 60-61 but again it was during the suckage period which began in the 40s and ended in 64-65. As said before i would not use that period as the wx patterns were very different across this region and elsewhere in general and thus not just my backyard. The winters in recent years have been nothing like back then. Hopefully we don't have to go through this again. Despite all of that i'll hold back on my excitement for now anyways. See how the next few month's go.

[Srain]

I noticed the Monday ENSO Update suggested neutral condition throughout tropical season. That should bode well for increasing tropical activity through October.

[HM]

Okay, that's certainly fair, that 15 is an important benchmark. The TNA is definitely a legitimate argument for at least as much activity as the years you referenced. I might say that the TNA would be a greater influence on the maximum intensity of storms, and thus the number of hurricanes and major hurricanes, versus named storms. I wouldn't say the QBO directly dictated the total number of NS in 2000, but it definitely influenced it IMO. Like I said, I think a very similar evolution to the season is possible. Very active early, and a slow Oct-Nov-Dec. 2000 was year 2 of La Nina, not 3, but point taken, and definitely a possible factor in slightly lower numbers.

Yeah the decent of the QBO easterlies has slowed a lot in the last month or so, so we'll see where we are by September. I don't think the QBO directly affects totals, but affects like you said the spatial distribution of storms, and also the temporal distribution, which when superimposed on climatology, has an effect on totals.

We'll see what happens. To make things interesting, I'll stick with my forecast until it's doomed to fail

I called 2000 year 3 because I care more about tendency than I do raw 3.4 values. By July-Aug 1998, we were basically La Niña in the coupled atmosphere/ocean system so I consider that first year. Now, in 2001 you could argue that we would be year 4 then because there was some minor cooling toward 2001-02 winter; however, there was also some warming May through August 20001 which I think helped the TNA out. Also the late winter -NAO helped, too...simply put: we were neutral with no tendency.

The simple fact is, the -OLR has been behaving like a +QBO so far (cross-tropopause shear induced convection) and the tropical waves across the Atlantic have been stealthy. In fact, 95L started as an Atlantic wave, which is impressive to me. By the time the -QBO starts legitimately affecting things, it may be too late to really even affect the spatial distribution (late autumn). Of course, I could be completely wrong here...

[HM]

June 20th weeklies

ENSO 1+2: +0.8 (+0.9)

ENSO 3 +0.2 (+0.2)

ENSO 3.4 -0.1 (0.0)

ENSO 4 -0.3 (-0.2)

* Values inside parenthesis denote Jun 13th weeklies

June 27th weeklies

ENSO 1+2: +0.4

ENSO 3 +0.3

ENSO 3.4 0.0

ENSO 4 -0.2

Seems like the waves have gotten dampened and things both atmospherically and in the water are kind of blah...neutral about sums it up perfectly.

[Amped]

Gotta love the GFSs back propagating phase1

[Typhoon Tip]

Kind of makes the dream of interstellar travel seem a bit fleeting and unattainable if every quantum scale fraction of our beings are inexorably linked to the vagaries of the sun

[HM]

Gotta love the GFSs back propagating phase1

The current CHI patterns are indicative of high frequency/low amplitude kelvin waves and they are generally a bore. The MJO has been dead since May; although, you could argue we have a very weak phase 8-1 response currently, despite the charts.