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Slow cooling in Nino 3.4 and 4 over the past month. August subsurface for 100-180W in the tropical pacific looks slightly negative.
The NAO has also come up recently to near neutral after spending mid-April to a few days ago in deep, consistent negative values.
The PDO also looks less canonically positive than a few days ago as the waters off Alaska cool some. Tropical Tidbits has Nino 1.2
warming like the weeklies do recently, with Nino 4 cooling off to +0.4 int he days after this time frame ended (centered on 8/21).
     
                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 24JUL2019     21.1-0.2     25.5 0.0     27.6 0.4     29.8 1.0
 31JUL2019     20.6-0.5     25.2-0.2     27.5 0.5     29.8 1.0
 07AUG2019     20.3-0.6     25.3 0.1     27.3 0.4     29.6 0.9
 14AUG2019     20.0-0.7     24.7-0.3     27.0 0.1     29.5 0.8
 21AUG2019     20.3-0.3     24.7-0.3     26.8 0.0     29.5 0.8
 27JUL2016     21.3 0.1     24.8-0.6     26.6-0.5     29.0 0.2
 03AUG2016     21.5 0.5     24.7-0.5     26.4-0.5     28.8 0.1
 10AUG2016     21.0 0.1     24.5-0.7     26.3-0.6     28.6-0.1
 17AUG2016     21.1 0.5     24.5-0.5     26.3-0.5     28.7 0.0
 24AUG2016     20.8 0.2     24.4-0.5     26.2-0.6     28.6-0.1
 26JUL2017     21.3 0.0     25.5 0.1     27.1 0.0     28.9 0.2
 02AUG2017     20.9-0.1     25.4 0.1     27.2 0.2     28.9 0.2
 09AUG2017     20.5-0.3     25.1 0.0     26.7-0.2     28.7 0.1
 16AUG2017     19.9-0.7     24.5-0.5     26.4-0.5     28.8 0.1
 23AUG2017     19.6-1.0     24.6-0.4     26.7-0.1     28.9 0.2
 25JUL2018     21.1-0.3     25.8 0.3     27.4 0.3     29.0 0.3
 01AUG2018     21.2 0.1     25.3 0.0     27.1 0.1     29.1 0.4
 08AUG2018     20.8-0.1     25.1-0.1     27.1 0.2     29.2 0.5
 15AUG2018     20.9 0.2     25.4 0.4     27.3 0.4     29.5 0.8
 22AUG2018     20.4-0.2     25.1 0.1     27.1 0.3     29.0 0.4
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You can play it both ways - Nino 1.2 and Nino 3 have warmed in recent days. Dorian has me looking at 1964...because of Dora. But it isn't similar at all. There is still a lot of warmth to be overcome in the Tropical Pacific. I have issues with 2013, but it the oceans are starting to look more like 2013 than prior months did. 2004/2013 with lower solar and some other adjustments is getting close to the look of recent months.

9hUB3o4.png

The July Jamstec had showed a cold Nino 3/3.4 in Sept-Nov burning off later. There is a lot of cool and warm subsurface water to swing Nino 3.4 around like a yo-yo for a while.

Qp7ORR9.png

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Kind of leaning toward this blend for Fall 2019 analogs. Not going to do a Fall forecast, my Summer analogs look fine for September still. I suspect I'll put in another low solar year and switch out 1992 or 2013 for winter, but we'll see.  The hurricane set to hit Florida from the east is a good omen for 1992/2004 having likeness to this year.

 

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3 hours ago, raindancewx said:

Kind of leaning toward this blend for Fall 2019 analogs. Not going to do a Fall forecast, my Summer analogs look fine for September still. I suspect I'll put in another low solar year and switch out 1992 or 2013 for winter, but we'll see.  The hurricane set to hit Florida from the east is a good omen for 1992/2004 having likeness to this year.

 

Image

Except we really don't know where it's gonna hit yet...so ya might wanna hold off on that, Analogon! (gonna start calling ya that because I've seen somebody dissect analogues to the minute detail you do! :lol:)

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My methods aren't that radical, I just blend in the actual weather conditions in the US with the background climate signals and run it all forward instead of using only weather or only background signals. Similar weather over a long period is usually an indicator of similar MJO tendencies if nothing else.

Florida was hit by a lot of hurricanes in 2004, and the SST pattern globally has been fairly similar to late Summer 2004. It probably won't last. A lot of years with a sudden NAO flip in mid-Summer also tend to see high Atlantic hurricane activity, and the NAO has been neutral/positive of late after the extended negative period.

I mentioned 1992 because the path is kind of like Andrew last I looked on the European, but also the 2004 and 1964 storms. That run due west into Florida is fairly rare if you look at historical tracks, were it to verify - it is a hint.

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On 8/29/2019 at 11:21 PM, Maestrobjwa said:

Except we really don't know where it's gonna hit yet...so ya might wanna hold off on that, Analogon! (gonna start calling ya that because I've seen somebody dissect analogues to the minute detail you do! :lol:)

I was very skeptical, but he did well last season. Still not my preferred methodology, but he def. has my attention this season.

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The subsurface data came in for August for 100-180W: -0.08, after being positive in July.

Closest years for Jun-Aug, in order, are 2000, 2017, 2008, 2003, 1987, 1996.

2017 should continue to fall off as a close match going forward, as the subsurface was much colder by August.

100-180W Jan Feb Mar Apr May Jun Jul Aug
2019 0.59 0.94 1.19 0.41 0.07 0.24 0.13 -0.08
2000 -1.28 -0.91 -0.64 -0.31 -0.18 0.08 0.03 0.00
2017 0.01 0.15 0.22 0.06 0.30 0.22 0.16 -0.40
2008 -1.50 -1.20 -0.45 0.02 0.17 0.38 0.42 -0.15
2003 0.27 -0.11 -0.06 -0.49 -0.85 0.13 0.53 0.03
1987 1.22 0.17 0.60 0.31 0.58 0.37 -0.10 0.20
1996 -0.29 -0.12 0.05 0.01 -0.16 0.17 -0.18 -0.35

Something like this is pretty close. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt

100-180W Jun Jul Aug
2000 0.08 0.03 0.00
2008 0.38 0.42 -0.15
2000 0.08 0.03 0.00
2008 0.38 0.42 -0.15
2000 0.08 0.03 0.00
Mean 0.20 0.19 -0.06
2019 0.24 0.13 -0.08

The surface was still borderline El Nino in August for Nino 3.4, although Nino 3 is pretty cold now.

VkDr7f6.png

Subsurface isn't super-strongly predictive for Nino 3.4 in DJF, in August, but I get 26.325C for Nino 3.4 in DJF using the Aug subsurface, and if you hindcast for 1979-2018, it should be within 0.7C of that 80% of the time - I'd call 27.0C and above an El Nino, and 26.0C or less a La Nina. The average error for the last 10-years is 0.4C from what the formula projects.

Closest SOI matches to Jun-Aug since 1931 include 1992 and 2004. Some very cold and snowy winters in that list for me, but should change a lot in Fall/Winter.

SOI Jun Jul Aug
1946 -8.8 -9.5 -4.0
1949 -10.9 -1.6 -4.0
1959 -5.3 -4.0 -4.0
1963 -10.2 -2.2 -2.8
1992 -11.9 -6.5 0.8
2004 -13.0 -6.4 -6.7
2019 -10.0 -5.9 -3.1

1959/1992/2004 as a blend is -10.1/-5.6/-3.3 - and almost exact match for this year. If you warmed it up 0.1C or so everywhere...not bad as a match for something purely SOI derived. 

etifth5.png

 

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Warmer than the 2017 La Nina through August, by around 0.4C according to the ECMWF. New forecast for September should be out soon. Nino 3 was near La Nina conditions but still Neutral, with Nino 1.2 near -1.0C for August on the ECMWF graphs. Nino 4 remained quite warm, around +0.8C warmer than in 2017 in August. To me, that's the difference between a La Nina winter and a Neutral winter, but we'll see.

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Getting close again...but Nino 3.4 fell of a cliff in Sept 2017 and had colder Nino 4 / subsurface conditions by now. We will see.

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 07AUG2019     20.3-0.6     25.3 0.1     27.3 0.4     29.6 0.9
 14AUG2019     20.0-0.7     24.7-0.3     27.0 0.1     29.5 0.8
 21AUG2019     20.3-0.3     24.7-0.3     26.8 0.0     29.5 0.8
 28AUG2019     20.2-0.4     24.6-0.3     26.5-0.2     29.2 0.6
 09AUG2017     20.5-0.3     25.1 0.0     26.7-0.2     28.7 0.1
 16AUG2017     19.9-0.7     24.5-0.5     26.4-0.5     28.8 0.1
 23AUG2017     19.6-1.0     24.6-0.4     26.7-0.1     28.9 0.2
 30AUG2017     20.3-0.2     24.5-0.4     26.5-0.2     28.8 0.2
 06SEP2017     20.4-0.1     24.3-0.6     26.2-0.6     28.7 0.1
 13SEP2017     19.7-0.7     24.0-0.9     26.1-0.6     28.7 0.0
 20SEP2017     19.3-1.1     23.9-1.0     26.3-0.4     28.7 0.0
 27SEP2017     19.5-1.0     24.4-0.5     26.5-0.2     28.4-0.2

 

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Closest matches for Nino 1.2, Nino 3, Nino 3.4, Nino 4 SSTs, for June, July, Aug are 1980, 1990, 1994, 2004, 2017, 2018.

ONI was +0.3 for JJA, with only a +0.03C reading for August 2019 in Nino 3.4. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/detrend.nino34.ascii.txt

2019   6   28.19   27.65    0.54
2019   7   27.65   27.26    0.39
2019   8   26.94   26.91    0.03

Compared to 1951-2010, 26.94C is actually +0.3C in Nino 3.4. The Nino 4 reading for August is most similar to El Ninos still.

1992 is very close for Nino 3.4 in Jun, Jul, Aug - top match since 1950. The 1991-92 El Nino lasted pretty late into 1992, before fading to a Neutral briefly in 1992-93 and the going to an El Nino in early 1993.

1992 28.30 27.51 26.91
2019 28.19 27.66 26.94

Look at your closest Nino 4 matches though - for Jun-Aug.

    Nino 4       Jun         Jul Aug
1987 29.37 29.38  29.38
1991 29.35 29.34 29.26
1994 29.23 29.40 29.50
1997 29.23 29.37 29.29
2002 29.61 29.52 29.43
2015 29.88 29.78 29.77
2019 29.58 29.66 29.44

My Summer Analogs were 1966, 1966, 1987, 1992, 1993, 2015. Not a terrible blend overall for the oceans or US high temps by month (cool Jun / hot west coast, then hot July/cool West coast, hot Aug, cold Northern Plains was the idea and more or less what happened). Nino 4 stayed even warmer than I had it, but Nino 3 / Nino 1.2 really cooled off a lot in August, although against 1951-2010 means, Nino 3 is still only -0.06C in August 2019.

Nino 4 Jun Jul Aug
1966 28.93 28.98 28.58
1966 28.93 28.98 28.58
1987 29.37 29.38 29.38
1992 29.24 29.21 28.93
1993 29.01 28.97 28.92
2015 29.88 29.78 29.77
Mean 29.23 29.22 29.03
       
2019 29.58 29.66 29.44
       
       
Nino 3.4 Jun Jul Aug
1966 27.64 27.33 26.48
1966 27.64 27.33 26.48
1987 28.65 28.59 28.42
1992 28.30 27.51 26.91
1993 28.08 27.52 26.99
2015 28.90 28.75 28.79
Mean 28.20 27.84 27.35
       
2019 28.19 27.66 26.94
       
Nino 3 Jun Jul Aug
1966 25.89 25.26 24.35
1966 25.89 25.26 24.35
1987 27.48 26.92 26.57
1992 27.17 25.75 25.03
1993 27.06 26.05 25.36
2015 28.07 27.66 27.21
Mean 26.93 26.15 25.48
       
2019 26.82 25.71 24.83
       
Nino 1.2 Jun Jul Aug
1966 21.57 20.67 19.83
1966 21.57 20.67 19.83
1987 24.10 22.98 21.82
1992 23.98 21.89 20.87
1993 24.16 22.66 21.57
2015 25.32 24.50 22.66
Mean 23.45 22.23 21.10
       
2019 22.78 21.27 20.20

 

 

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                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 07AUG2019     20.3-0.6     25.3 0.1     27.3 0.4     29.6 0.9
 14AUG2019     20.0-0.7     24.7-0.3     27.0 0.1     29.5 0.8
 21AUG2019     20.3-0.3     24.7-0.3     26.8 0.0     29.5 0.8
 28AUG2019     20.2-0.4     24.6-0.3     26.5-0.2     29.2 0.6
 04SEP2019     19.8-0.6     24.9 0.0     26.6-0.2     29.1 0.5

Nino 3 warmed up a bit this week. Well behind 2017 for cold at this point, except in Nino 1.2 which is volatile. 

 09AUG2017     20.5-0.3     25.1 0.0     26.7-0.2     28.7 0.1
 16AUG2017     19.9-0.7     24.5-0.5     26.4-0.5     28.8 0.1
 23AUG2017     19.6-1.0     24.6-0.4     26.7-0.1     28.9 0.2
 30AUG2017     20.3-0.2     24.5-0.4     26.5-0.2     28.8 0.2
 06SEP2017     20.4-0.1     24.3-0.6     26.2-0.6     28.7 0.1

CFS & Canadian have essentially opposite winter forecasts right now, with the CFS warm almost everywhere for SSTs and the new Canadian cold almost everywhere. 

The Weatherbell guys like a blend of 2013-14/2014-15 or 2013-14 (x3), 2014-15, 2018-19. That gives you a cold eastern tropical Pacific, with a warm western tropical Pacific. I have some issues with it as a blend, but it does look close to current SSTs. The West is generally wetter in winters after El Ninos for one. The sea ice was also a lot higher in 2013/2014 at the minimum extent in September. Also think Nino 4 will be a lot warmer than that blend, but we'll see. The ECMWF Nino 3.4 Sept 1 forecast updated should be out any day now, and the Jamstec is likely later in the week too.

 December_2019_February_2020_Forecast.png

Winter_2019_20_Snowfall.png

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Latest European run has warmed a bit. I drew in yellow what I expect in Nino 3.4. At this point in recent years, the Euro September Nino 3.4 forecasts were pretty good.

The SOI has been very negative in September so far, which means we should avoid La Nina conditions at least. Very hard to get below a -5 or -10 SOI in September and then a La Nina the following winter. The SOI should remain predominantly negative through at least 9/17. These are the Septembers since 1931 with a -4 to -12 SOI...it is actually currently at -16 for 9/1-9/10. The 1946 and 1932 ENSO winters were preceded by SOI Septembers under -8 and both were cold Neutrals, but almost all the others are El Ninos.

Sept SOI
1976 -12.4
1951 -11.2
1987 -10.6
1969 -10.0
1957 -9.4
1939 -8.8
1977 -8.8
2018 -8.5
1932 -8.3
1941 -7.7
1990 -7.3
2002 -7.3
1948 -7.1
1993 -7.0
2014 -6.6
1934 -5.9
1963 -5.9
1980 -4.7
1986 -4.7
2006 -4.6
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August PDO data:

2019-01-01T00:00:00Z 0.66
2019-02-01T00:00:00Z 0.46
2019-03-01T00:00:00Z 0.37
2019-04-01T00:00:00Z 1.07
2019-05-01T00:00:00Z 1.03
2019-06-01T00:00:00Z 1.09
2019-07-01T00:00:00Z 1.03
2019-08-01T00:00:00Z 0.38

 

August AMO data:

 2017    0.222    0.224    0.164    0.280    0.311    0.305    0.299    0.307    0.347    0.430    0.349    0.361
 2018    0.170    0.059    0.129    0.061   -0.004   -0.014    0.015    0.110    0.159    0.141   -0.124   -0.063
 2019   -0.018    0.078    0.118    0.121    0.085    0.171    0.349    0.335
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