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On 11/22/2017 at 13:06, jvenge said:

Maybe @Tamara can correct, but I don't think the MJO phases of December 2010 were responsible for the severe cold in that month. Wasn't it amplification that took place in October/early November, which lead to a very cold start to December, which was responsible for the November/December cold spell and wasn't it then the La Nina influence that put an end to it?

 

So, maybe it is just me, but I find his December comparison to be way off the mark and the linking of the analog also off the mark.

That MJO wave will have increased AAM but it looks like it was so weak that any effect would have been short and muted (perhaps being something that helped us get a cool January rather than the horror of February). It was indeed the high amplitude wave in October which helped us in our cause. 

I suspect the poster was talking about timing though which is very similar this year. If we want the blocking to continue though then we will be looking for a much higher amplitude to the MJO progression in December even if this means suffering through the mild phases. If the MJO is as muted as 2010 then it means the Pacific Trades (La Nina) have won and we'll see the pattern wane unless any SSW saves us. 

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Regarding the correlation between La Nina and North Atlantic and western European weather, something I find quite difficult to pin down, if indeed it can be pinned down, this paper may be of interest assuming it hasn't been posted already over the last two or three years. Or indeed it may not be

Impacts of two types of La Niña on the NAO during boreal winter

Quote

The present work identifies two types of La Niña based on the spatial distribution of sea surface temperature (SST) anomaly. In contrast to the eastern Pacific (EP) La Niña event, a new type of La Niña (central Pacific, or CP La Niña) is featured by the SST cooling center over the CP. These two types of La Niña exhibit a fundamental difference in SST anomaly evolution: the EP La Niña shows a westward propagation feature while the CP La Niña exhibits a standing feature over the CP. The two types of La Niña can give rise to a significantly different teleconnection around the globe. As a response to the EP La Niña, the North Atlantic (NA)–Western European (WE) region experiences the atmospheric anomaly resembling a negative North Atlantic Oscillation (NAO) pattern accompanied by a weakening Atlantic jet. It leads to a cooler and drier than normal winter over Western Europe. However, the CP La Niña has a roughly opposing impact on the NA–WE climate. A positive NAO-like climate anomaly is observed with a strengthening Atlantic jet, and there appears a warmer and wetter than normal winter over Western Europe. Modeling experiments indicate that the above contrasting atmospheric anomalies are mainly attributed to the different SST cooling patterns for the two types of La Niña. Mixing up their signals would lead to difficulty in seasonal prediction of regional climate. Since the La Niña-related SST anomaly is clearly observed during the developing autumn, the associated winter climate anomalies over Western Europe could be predicted a season in advance.

https://link.springer.com/article/10.1007/s00382-014-2155-z  (open access

Edited by knocker
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Cooling is more in ‘moderate’ territory in the eastern side of the ENSO region. I wonder if this could do with toning down to ‘weak’ territory for a colder NW Europe?

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Will be interesting to see where we head ENSO wise as we head towards summer.

Historically I believe summers coming off the back off a winter Nina tend to be poor. Would certainly fit the narrative of the '8' summer.

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On 1/3/2018 at 18:14, CreweCold said:

Will be interesting to see where we head ENSO wise as we head towards summer.

Historically I believe summers coming off the back off a winter Nina tend to be poor. Would certainly fit the narrative of the '8' summer.

Statistically speaking the highest chance of hot CET month comes overwhelmingly from warm-neutral/weak Nino though even they are no guarantee. 

At any rate i would certainly not rule out a multi-year Nina even if not too strong and gappy. 

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2 minutes ago, summer blizzard said:

Statistically speaking the highest chance of hot CET month comes overwhelmingly from warm-neutral/weak Nino though even they are no guarantee. 

At any rate i would certainly not rule out a multi-year Nina even if not too strong and gappy. 

I felt last summer was THE chance of recent years to have a hot summer...given the descent from Nino into ENSO neutral conditions during the 12 months previous.

 

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Post-Nina summers also have a habit of being unkind to the Arctic sea ice. Given it's at record lows for extent right now and lacking in much thick multi-year ice, I wonder if 2018 might be a bit of a villainous year from a climatic perspective :bomb::unsure2:.

Speculative of course (to the max!).

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49 minutes ago, CreweCold said:

I felt last summer was THE chance of recent years to have a hot summer...given the descent from Nino into ENSO neutral conditions during the 12 months previous.

 

Tendency would always suggest bad in that regard, you'd want to be headed from and towards. 2014 was probably the missed one in that regard. 

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This year's hurricane season... well, let's just say we could do with the current SST pattern in the MDR and subtropics becoming less supportive of tropical cyclone development by August or ideally sooner than that!

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Personally i am suspicious of any forecast for a developing El Nino now that the 2015/2016 westerlies have been scrubbed.

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Hi. Can anybody tell what effects a El Nino Modoki Winter have for the United Kingdom/ Western Europe??  And when was the last time we had such conditions??  Thanks

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I think La Nada will take care of the summer but then how will global temps impact the region come late autumn?

I'm not looking for any development until we're in 2019 but the harvesting of heat this summer may well add into the nino to come?

I do believe that the next Nino will shadow what we saw in 15/16 with other drivers pumping up global temp along with the nino so folk will again be calling it a 'Super Nino'?

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Nina weakening however region 1.2 saw it's coldest January since 1981. 

Personally i actually expect Nina to return somewhat like 2017 in the summer/Autumn. 

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The current S.American heatwave might impact the current temps in regions 1 & 2 as any associated surface warming travels north?

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index.php?action=dlattach;topic=2228.0;attach=97961;image

Agreed Knocks! the anomaly at the date line just gets bigger and bigger?

I think when QBO flips back we might see another sizable event build ( 2019?)

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A weak Nina remains with both 1.2 and 3.4 recording -0.7.

There is warm water under the sub-surface but the MJO has now entered the circle of death so the death of Nina is probably still at least a month away. 

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2 minutes ago, summer blizzard said:

A weak Nina remains with both 1.2 and 3.4 recording -0.7.

There is warm water under the sub-surface but the MJO has now entered the circle of death so the death of Nina is probably still at least a month away. 

For impacts, yes....seems to have a month of life left into it. Current model projections seem to be going towards neutral after that.

For cold weather lovers, a move towards an El Nino for the winter would be preferred. In the mean time, for a good Spring and Summer, the demise of the La Nina should be wished for.

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