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Weak La Nina Winter


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The most interesting this about this winter to me is going to how the Modoki status plays out. The JAMSTEC is down right now, but the Modoki definition they use implies if Nino 3.4 is substantially cooler than the Eastern/Western Tropical Pacific as the CFS & Canadian show for DJF, that it will be the shape of a Modoki La Nina winter, kind of with a traditional El Nino blended in (since the Eastern Pacific will be warmer) for a Neutral/Cold Neutral DJF.

I believe when the Jamstec was last up, it was showing a warm Neutral with a positive Modoki reading, i.e. Nino 3.4 warmer than the Eastern/Western Pacific and not cooler. 

These winters are very different for the US though:

Nino 3.4 = -0.2, East Pacific = +0.1, West Pacific = +0.1, Modoki = -0.2

Nino 3.4 = -0.2, East Pacific = -0.2, West Pacific = -0.2, Modoki = 0.0

Nino 3.4 = -0.2, East Pacific = -0.4, West Pacific = -0.4, Modoki = 0.2

The third scenario is probably coldest for the East, and it is what we have now...sure enough with a fair amount of cold east of the Rockies.  

Today, Tropical Tidbits has Nino 3.4 at -0.1. Nino 1.2 is -1.0, and Nino 4 is +0.1 (proxy for what the Jamstec uses), so you'd get:  Modoki = -0.1 - (-1.0*0.5)-(0.1*0.5), or a Modoki value of +0.35.

The first scenario is what the models seem to believe though, and that would favor cold in the West or Central part of the US. I have no idea which to believe at this point. La Nina winters do tend to have negative Modoki values, while Neutrals are usually positive Modoki values, barring low-solar activity, which of course we have this year.  El Ninos are usually positive Modoki values, but obviously some are not, i.e. 1982, 1997, etc.

Modoki Index Definition.PNG

Modoki Index Definition 2.png

5992639ab8629_ModokiDefinition3.thumb.png.f70232ad419dae00c160c90c1b4891cd.png

 

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I don't really have anything to add. Wanted to throw in what the latest Jamstec has though. The Jamstec uses a 1983-2006 base period, so it is missing large parts of the 1982-83 El Nino and of the 2006-07 El Nino, and then the big El Nino of 2009-2010 entirely, that are included in NOAA's 30-year base period - 1981-2010.

So I like to lower the Jamstec numbers by 0.2C to get it equivalent to NOAA. So it shows roughly -0.1C for DJF now? Down from +0.3C or so before.

 

 

Jamstec ENSO Forecast 8.22.17.gif

El Nino Modoki Fcst 1.JPG

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With Harvey about to make landfall relatively close to where the 1932 Freeport Hurricane hit, at about the same time of year (Aug), and about the same strength (4) definitely going to be leaning on using that as an analog going forward. 1932 had a nice warm up in an ONI sense from winter to summer before the ONI fell off again in summer to winter. Solar cycle is very similar, ENSO sequence is similar, AMO/PDO/Modoki transitions all look similar. ONI got to +0.4C in Spring / Summer 1932 before falling off to -0.2 / -0.3 the next Winter / Spring. Seems similar to this year give or take 0.2C.

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10 hours ago, raindancewx said:

With Harvey about to make landfall relatively close to where the 1932 Freeport Hurricane hit, at about the same time of year (Aug), and about the same strength (4) definitely going to be leaning on using that as an analog going forward. 1932 had a nice warm up in an ONI sense from winter to summer before the ONI fell off again in summer to winter. Solar cycle is very similar, ENSO sequence is similar, AMO/PDO/Modoki transitions all look similar. ONI got to +0.4C in Spring / Summer 1932 before falling off to -0.2 / -0.3 the next Winter / Spring. Seems similar to this year give or take 0.2C.

using the mei scale 1930-31 was a strong el nino...1931-32 was a neutral positive...1932-33 was a weak negative...snowfall for 1932-33 was near average in NYC...1932-33 followed two mild winters like this year....1932-33 was a mild winter...snowfall in DCA was 24"...

1932 33.png

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Weekly & Daily ONI values have recovered to -0.1C according to both NOAA & Tropical Tidbits. August looks around -0.2C to me with the brief warm Neutral spell and brief La Nina spell cancelling out to cold Neutral. September may cool further, but August was warm enough that JAS won't see La Nina conditions like last year.

http://www.cpc.ncep.noaa.gov/data/indices/wksst8110.for

In an anomaly sense, August looks 0.6C or 0.7C colder than May - so would expect JJA to be +0.1C / +0.0C / -0.1C.  Still warmer than last JJA which was -0.3C.

 

ONI August.png

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^^ One of the reasons I've been stubborn on not going La Nina is that cold pool is going to Nino 1.2 more than Nino 3.4. If Nino 1.2 is cool this year though, instead of +0.7C like last winter the East will be cooler and my area will be drier.

Was playing with this as an early look at winter values, using my system which is programmed to automatically score all years for 1931-2016 based on similarity to expected/entered winter conditions, with matching weather (monsoon rain here):

"Cold Scenario" --> One-two trimester periods of ONI at -0.5 to -1.0. The modoki values are negative when the central Pacific - (0.5)(western Pacific) - (0.5)(eastern pacific) values in the tropics are negative - its Modoki La Ninas and East Based El Ninos. Last winter was a -0.48 Modoki, with the east Pacific warm making it very strongly in the Modoki camp. The weightings below are partially based on getting everything within range, including my rainfall in Summer. 

Year ONI DJF PDO N-A AMO N-A Sun Jul-Jun ONIp DJF Modoki? Monsoon Analog Weight
1931 -0.3 0.38 0.186 25.1 1.3 -0.29 3.54 x1
1932 -0.2 -0.08 0.134 14.5 -0.3 -0.01 5.08 x5
1943 -0.1 0.34 0.294 14.2 -1.4 -0.17 3.74 x2
1944 -0.5 -0.10 0.329 33.8 -0.1 -0.28 4.46 x2
1962 -0.4 -0.46 0.144 42.2 -0.2 0.11 2.14 x3
1995 -0.9 0.62 0.029 14.9 1.0 -0.20 3.61 x1
1996 -0.5 0.38 -0.058 14.5 -0.9 0.22 6.80 x2
2005 -0.9 0.14 0.154 34.7 0.6 -0.26 4.39 x1
2007 -1.5 -0.94 0.127 7.2 0.7 -0.89 3.41 x3
Aggregate -0.55 -0.11 0.15 21.02 -0.10 -0.18 4.18 x20
Goal -0.70 0.25 0.150 18.00 -0.40 -0.20 3.75

 

Cool (A few periods at -0.3, -0.4, -0.5)

Year ONI DJF PDO N-A AMO N-A Sun Jul-Jun ONIp DJF Modoki? Monsoon Analog Weight
1931 -0.3 0.38 0.186 25.1 1.3 -0.29 3.54 x1
1932 -0.2 -0.08 0.134 14.5 -0.3 -0.01 5.08 x4
1943 -0.1 0.34 0.294 14.2 -1.4 -0.17 3.74 x3
1962 -0.4 -0.46 0.144 42.2 -0.2 0.11 2.14 x2
1985 -0.5 1.02 -0.290 16.1 -1.0 -0.09 4.71 x1
1996 -0.5 0.38 -0.058 14.5 -0.9 0.22 6.80 x1
2007 -1.5 -0.94 0.127 7.2 0.7 -0.89 3.41 x1
Aggregate -0.36 0.05 0.129 19.07 -0.44 -0.11 4.18 x13
Goal -0.40 0.00 0.150 18.0 -0.40 -0.20 4.15  

 

DJQlHufVwAAcPrP.jpg

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The European and Jamstec are both on board now - I've given up. It's interesting though, the CFS/Jamstec/EURO all have Nina collapsing pretty quickly in Spring even though they show it at -0.5 to -1.0C which is a pretty healthy peak. The JAS ONI value to me looks like like -0.4C give or take 0.1C. But its near certain ASO and beyond will be in La Nina territory now.

Pattern may end up a relaxed version of last year overall - still a Modoki La Nina, but Nino 1.2 with less cold values than Nino 3.4 instead of very warm values. 

I'm in the SW - La Nina winters that follow La Nina winters are a bit different than those that follow El Nino winters - often colder/snowier in Nov-Dec, and then kind of similar after that. Atlantic is colder than last year too, with Harvey/Irma/Jose/Katia and the new waves all producing some cold wakes. Sun is weaker too. So its all a bit different from last year. PDO won't be super positive either.

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7 hours ago, raindancewx said:

The European and Jamstec are both on board now - I've given up. It's interesting though, the CFS/Jamstec/EURO all have Nina collapsing pretty quickly in Spring even though they show it at -0.5 to -1.0C which is a pretty healthy peak. The JAS ONI value to me looks like like -0.4C give or take 0.1C. But its near certain ASO and beyond will be in La Nina territory now.

Pattern may end up a relaxed version of last year overall - still a Modoki La Nina, but Nino 1.2 with less cold values than Nino 3.4 instead of very warm values. 

I'm in the SW - La Nina winters that follow La Nina winters are a bit different than those that follow El Nino winters - often colder/snowier in Nov-Dec, and then kind of similar after that. Atlantic is colder than last year too, with Harvey/Irma/Jose/Katia and the new waves all producing some cold wakes. Sun is weaker too. So its all a bit different from last year. PDO won't be super positive either.

But haven't we seen a big uptick in solar activity with the solar flares over the past few weeks? They were the biggest ones in over a decade with northern lights being seen as far south as Little Rock, Arkansas.

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8 hours ago, Paragon said:

But haven't we seen a big uptick in solar activity with the solar flares over the past few weeks? They were the biggest ones in over a decade with northern lights being seen as far south as Little Rock, Arkansas.

I wouldnt really call a strong solar flare, release of energy, an uptick in solar activity.

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There has been a bit of an increase in sunspot activity in Aug-Sept via SILSO, but it seems to be decreasing rather rapidly toward the low levels it has been at prior to August. Sept 1-16 is around 60 sunspots per day, but it was 80 for Sept 1-10. Suspect we get down to 35 or so by the end of the month. July 2016-June 2017 had 28.5 sunspots/month. I've been assuming 18 sunspots for July 2017-June 2018 based on historical decay rates given the minimum should be in 2019-2020 (absolute min around NYE 2020?).

Its interesting to me that the SOI hasn't really responded to the La Nina either - the readings were +6.5 in July and +3.5 in August. Last 30 days are +5.7. Would expect a +8 at least if this is going to get -0.6C or so for Aug-Oct ONI?

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High chance this lasts through the Winter, possibly Moderate La Nina officially. I did research that shows the subsurface is actually higher correlated to the Northern Hemisphere pattern than surface SSTs. By such a margin that you could estimate the surface actually has zero effect, because the correlation with subsurface measurement was so high (Ex: subsurface is 0.85 correlated, surface 0.70, but subsurface and surface are 0.90 correlated).

This is subsurface Moderate La Nina, and the Atlantic Tropics are really showing this. 

wkxzteq_anm.gif

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I'm still pretty sold on using 1932-33 as an analog - Harvey/Freeport, Irma/Fl-AL hurricane, and Maria/San Ciprican are all almost identical in terms of timing and strength in the Atlantic. It's not like PR or TX get hit by cat fours real often.

1928-1962 was a warm AMO era like now. The raw AMO value for August 1932 was 23.502 - August 2017 was 23.661. If you assume +/-0.1 for the early observation years, its amazingly close. Solar is very close to 1932. PDO isn't bad August 1932 was -0.1, with August 2017 at +0.1.

1932 was two years after the big 1930-31 El Nino, ala this year which is two years after 2015-16. 1929-30 & 2014-15 were both very weak El Ninos. NOAA's ONI data assumes that Nino 3.4 has warmed 0.3-0.4 since 1950, so I think it's pretty likely that 1932-33 actual SST values were also very close to now too, it's just back then it would have been considered Neutral using NOAAs updating 30-year mean centering for deriving anomalies.

https://pbs.twimg.com/media/DKS8WhyVAAAb3KN.jpg:large

https://t.co/ZN4Gq3Vlxx

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In a weak La Nina Winter.....

 

Washington DC will enjoy cold spell after cold spell, each cold spell will moderate just enough to bring lots of rain, then cold again. Rinse and repeat about 900 times thru April 2018, then hot as hell.

For New England - a completely different story. For them, heavy snowstorm after heavy snowstorm after heavy snowstorm. All of the Miller B's that got going too late for DCA, will slam HARD into New England with crippling amounts of torrential snow, even by New England standards. Send in the National Guard to dig them out, they cant handle that kind of snow in New England - they dont have The Jebman to dig em out. In the New England ski resorts - many face shot days, in fact, MONTHS of face shot days when the instructors will get all hyper about the extremely deep pow! Better get a snorkel!

In a weak Nina winter, go northeast to see snow, or go to the heights of the Rockies to see snow, or save yourself a ton of trouble, and just go to the North Pole. Or Greenland.

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ONI weekly value rose to -0.4C. Nino 3.4 is third.

 07JUN2017     23.1-0.1     26.9 0.3     28.1 0.4     29.3 0.5
 14JUN2017     22.9 0.0     26.7 0.2     28.2 0.5     29.4 0.6
 21JUN2017     22.9 0.3     26.7 0.4     28.3 0.7     29.5 0.7
 28JUN2017     22.8 0.4     26.5 0.4     28.1 0.7     29.4 0.6
 05JUL2017     21.7-0.3     26.1 0.2     28.0 0.6     29.4 0.6
 12JUL2017     21.8 0.0     26.1 0.4     27.8 0.5     29.3 0.5
 19JUL2017     21.4-0.1     25.7 0.2     27.6 0.4     29.2 0.4
 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
 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

Are these big rises in SSTA going to continue on and off all winter? Seems somewhat unstable - Tropical Tidbits has Nino 3.4 back to -0.5C after a low of -0.9C around Sept 11, it's been rising slowly each day for two weeks now. Have little doubt a fall is coming, but each negative SOI burst since July has been accompanied by a slowdown or reversal in the trend to La Nina. 

nino34.png

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