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Gray-Wolf

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Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

23SEP2020 1.2: -0.8, 3.4: -1.0

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Posted
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow
  • Weather Preferences: continental climate
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow

@sebastiaan1973 @summer blizzard Despite some noise elsewhere this is not going to be a Modoki/CP Nina by definition. You can see the timeline on this Hovmoller chart of various Nina events EP,CP and mixed Ninas. It this was by Zhang definition  a CP Nina the coldest anomalies would have started in region 3.4 instead of 1.2 like this summer. At worst by definition we cam call this a mixed Nina if not EP. The coldest anomalies would have to be markedly cooler by now in region 4.

cdas-sflux_ssta_relative_global_1.png

EjMnkS0WAAAomZF.png

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Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
6 hours ago, sebastiaan1973 said:

Thanks. Is it not better to show some context? 

Weekly number, forgot to post on Monday.

Zone 1.2 is east, 3.4 is west.

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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
16 hours ago, jules216 said:

@sebastiaan1973 @summer blizzard Despite some noise elsewhere this is not going to be a Modoki/CP Nina by definition. You can see the timeline on this Hovmoller chart of various Nina events EP,CP and mixed Ninas. It this was by Zhang definition  a CP Nina the coldest anomalies would have started in region 3.4 instead of 1.2 like this summer. At worst by definition we cam call this a mixed Nina if not EP. The coldest anomalies would have to be markedly cooler by now in region 4.

cdas-sflux_ssta_relative_global_1.png

EjMnkS0WAAAomZF.png

Colder winter, here we come then if this ends up EP La Nina

Combine this with low solar output and the -IOD and a cooling N Pacific

Also having colder waters near the UK itself is a good thing as this means the cold is moderated less when it does come

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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
14 hours ago, summer blizzard said:

Weekly number, forgot to post on Monday.

Zone 1.2 is east, 3.4 is west.

I would have thought regions 1+2 and 3 would count as east as 1+2 is such a small zone and only covers the waters near to S America whilst region 3 is the general E Pacific region. 3.4 would be more central and 4 would be west

Nino 4 -0.5

Nino 3.4 -1.0

Nino 3 -1.2

Nino 1+2 -0.8

That to me looks like a mixed La Nina but more focused to the east of central. Could go either way at present. All regions are now La Nina so the base level La Nina is basin wide but the focus of the cold is Nino 3

Untitled.thumb.jpg.8e1544107283d3d54ad2be1ffe4ae8e4.jpg

On this chart the CP La Nina would have the core of the coldest anomalies within the red circle and this currently isn't the case.

The EP La Nina is more focused within the orange circle region and this is where the coldest anomalies have been in recent weeks

Edited by SqueakheartLW
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Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

ONI value for JAS was -0.6.

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Posted
  • Location: Edmonton Alberta(via Chelmsford, Exeter & Calgary)
  • Weather Preferences: Sunshine and 15-25c
  • Location: Edmonton Alberta(via Chelmsford, Exeter & Calgary)
On 02/10/2020 at 03:01, SqueakheartLW said:

Colder winter, here we come then if this ends up EP La Nina

Combine this with low solar output and the -IOD and a cooling N Pacific

Also having colder waters near the UK itself is a good thing as this means the cold is moderated less when it does come

to my untrained eyes looking similar to the 2010 la nina event ..therefore for the UK if current conditions hold sway and the added solar min i would go for a front loaded winter for the UK..early Dec to mid Jan..possibly something similar to Dec81- Jan 82 

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https://www.cpc.ncep.noaa.gov/products/CFSv2/imagesInd3/nino34Mon.gif

Can't take CFS enso forecast seriously. -3 (-0.9 colder than 1974) on 3 ensembles? This is beyond ridiculous.

Anyway, I checked what was the average and maximum temperature drop from JAS value to the pick each year:

None of the La ninas went below 0.9 degrees temperature, Thus three months of strong La nina seems to be extremely unlikely for our current event.

The overall average drop is -0.541. The average drop when JAS was within the range of -0.4 till -0.8: -0.427.

 

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Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

While i generally agree its worth pointing to 1970 and 2007 as first year Nina's which developed at a similar pace in Q3 but got too strong. 

September ONI will come in around -0.9 which with August should bring ASO to -0.8 without any weakening and probably higher if we assume continued strengthening through October. 

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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
7 hours ago, noname_weather said:

https://www.cpc.ncep.noaa.gov/products/CFSv2/imagesInd3/nino34Mon.gif

Can't take CFS enso forecast seriously. -3 (-0.9 colder than 1974) on 3 ensembles? This is beyond ridiculous.

Anyway, I checked what was the average and maximum temperature drop from JAS value to the pick each year:

None of the La ninas went below 0.9 degrees temperature, Thus three months of strong La nina seems to be extremely unlikely for our current event.

The overall average drop is -0.541. The average drop when JAS was within the range of -0.4 till -0.8: -0.427.

 

ENSO Criteria 1 = Region 3.4 - EL NINO

5 tri monthly periods at or above 0.5C = El Nino

Within this Criteria 2 must be met for strength of El Nino = Region 3.4

No more than 2 tri monthly periods of the 5 at or above 1.0C = Weak El Nino

Example Weak El Nino     1976 ASO:0.6 SON:0.8 OND:0.9 NDJ:0.8 1977 DJF:0.7 JFM:0.6

All figures in the 1976/77 El Nino remain at or above 0.5C but all remain below 1.0C so classifying this El Nino as a weak event

3 tri monthly periods of the 5 at or above 1.0C = Moderate El Nino

Example Moderate El Nino     1963 MJJ:0.5 JJA:0.9 JAS:1.1 ASO:1.2 SON:1.3 OND:1.4 NDJ:1.3 1964 DJF:1.1 JFM:0.6

All figures in the 1963/64 El Nino remain at or above 0.5C but 6 tri monthly periods equal or exceed 1.0C but remain below 1.5C so classifying this El Nino as a moderate event.

3 tri monthly periods of the 5 at or above 1.5C = Strong El Nino

Example Strong El Nino     1965 AMJ:0.5 MJJ:0.8 JJA:1.2 JAS:1.5 ASO:1.9 SON:2.0 OND:2.0 NDJ:1.7 1966 DJF:1.4 JFM:1.2 FMA:1.0 MAM:0.7

All figures in the 1965/66 El Nino easily meet the criteria of El Nino. 5 tri monthly figures equal or exceed 1.5C so easily a strong El Nino event. 2 of the figures get to 2.0C which is Super Nino levels but only 2 figures means the event gets classified as strong only

3 tri monthly periods of the 5 at or above 2.0C = Super Nino

Example Super Nino     2014 OND:0.6 NDJ:0.7 2015 DJF:0.6 JFM:0.6 FMA:0.6 MAM:0.8 AMJ:1.0 MJJ:1.2 JJA:1.5 JAS:1.8 ASO:2.1 SON:2.4 OND:2.5 NDJ:2.6 2016 DJF:2.5 JFM:2.2 FMA:1.7 MAM:1.0 AMJ:0.5

All figures in this long 2014 to 2016 El Nino event easily equal or exceed 0.5C so a definite El Nino event. Although it takes time to get going so therefore gives 2014/15 section a weak classification it is the 2015/16 event that gets the Super Nino classification with 6 tri monthly periods equalling or exceeding 2.0C. This was the strongest El Nino on record in the NINO 3.4 region.

The reverse holds true for La Nina

ENSO Criteria 1 = Region 3.4 - LA NINA

5 tri monthly periods at or below -0.5C = La Nina

Within this Criteria 2 must be met for strength of La Nina = Region 3.4

No more than 2 tri monthly periods of the 5 at or below -1.0C = Weak La Nina

Example Weak La Nina     2017 SON:-0.7 OND:-0.9 NDJ:-1.0 2018 DJF:-0.9 JFM:-0.8 FMA:-0.6

A perfect recent example of a weak La Nina, 2017/18. All 6 months are at or below -0.5C so makes it into a classified La Nina but with only 1 month getting to -1.0C then this keeps the event as a weak La Nina

3 tri monthly periods of the 5 at or below -1.0C = Moderate La Nina

Example Moderate La Nina     2011 JJA:-0.5 JAS:-0.7 ASO:-0.9 SON:-1.1 OND:-1.1 NDJ:-1.0 2012 DJF:-0.8 JFM:-0.6 FMA:-0.5

The most recent example of a moderate La Nina event is 2011/2012. 9 months meet the La Nina threshold so easily a La Nina event. However 3 months equal or exceed -1.0C so this La Nina event just scrapes a moderate classification.

3 tri monthly periods of the 5 at or below -1.5C = Strong La Nina

Example Strong La Nina     2010 MJJ:-0.6 JJA:-1.0 JAS:-1.4 ASO:-1.6 SON:-1.7 OND:-1.7 NDJ:-1.6 2011 DJF:-1.4 JFM:-1.1 FMA:-0.8 MAM:-0.6 AMJ:-0.5

What better year to go for a strong La Nina than the very year before the above moderate La Nina example, 2010/11. This one features a full years worth of tri monthly periods at or below -0.5C so easily a La Nina event. It however also features 4 tri monthly periods equalling or exceeding -1.5C so this is classified as a strong La Nina event

3 tri monthly periods of the 5 at or below -2.0C = Super Nina

There are no current Super Nina's on the record going back to 1950 but this doesn't mean we haven't had any in the past and doesn't mean we will never see one either. If CFS is to be believed then we will see our first Super Nina on the record this winter.

Edited by SqueakheartLW
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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe

Latest calculated tri monthly anomaly based on latest data from the following data link

https://www.cpc.ncep.noaa.gov/data/indices/sstoi.indices

JAS     NINO Region 4     -0.21    ENSO Neutral Colder Side (Just)

JAS     NINO Region 3.4  -0.63    Weak La Nina

JAS     NINO Region 3     -0.76    Weak La Nina

JAS     NINO Region 1+2 -0.98    Weak La Nina (Almost Moderate)

Looks like a definite weak east based La Nina at present based on JAS tri monthly period

If we take the individual month of September then the latest monthly anomalies are as follows:

NINO Region 4                -0.41     ENSO Neutral Colder Side

NINO Region 3.4             -0.95     Weak La Nina

NINO Region 3                -1.27     Moderate La Nina

NINO Region 1+2           -0.86     Weak La Nina

It looks as if moderate La Nina threshold has been reached in NINO Region 3 with Weak La Nina in Regions 3.4 and 1+2. NINO 4 is at ENSO Neutral on the colder side for September 2020.

This should still be classed as an east based La Nina since NINO Region 3 is basically the eastern portion of the pacific away from the immediate coast of S America which is where the small NINO Region 1+2 is.

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Posted
  • Location: Linford, Essex
  • Location: Linford, Essex
Just now, sebastiaan1973 said:

Latest calculations from Glosea5. Very strong La Nina. Quite a large area with an anomaly of  -2c or less.

Is this realistic?

2cat_20201001_sst_months24_global_deter_public.png

Out of all the charts being posted lately, as it's showing the outcome we least want, it's probably the one that's going to prove to be on the money.

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Posted
  • Location: Herne Bay, Kent (14 m)
  • Weather Preferences: Thunderstorms & Snow
  • Location: Herne Bay, Kent (14 m)

image.thumb.png.3ea83c5494208a6f7e6bc47fa19e541f.png   image.thumb.png.6193bb9c86cde151eb2e0ae9e166243e.png     image.thumb.png.fd7f32aad7fafd45c384e6f8458065dc.png    image.thumb.png.e862fd6922772124757b58f172b20308.png

La Nina ensembles from GLOSEA earlier.

Edited by Jamiee
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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
5 hours ago, Wynter said:

Out of all the charts being posted lately, as it's showing the outcome we least want, it's probably the one that's going to prove to be on the money.

The CFSv2 is going for a super Nina and possibly the strongest on record.  Lets hope they are over doing it, otherwise winter will very likely be another mild one!

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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
2 hours ago, Don said:

The CFSv2 is going for a super Nina and possibly the strongest on record.  Lets hope they are over doing it, otherwise winter will very likely be another mild one!

At the moment we have a weak to moderate East based La Nina and this probably is playing a big part in all the northern blocking we are seeing at the moment.

If the CFSv2 comes off then all that blocking is going to rapidly disappear before winter and it will very likely end up like last winter with another boring zonal mild washout

On the plus side a Super Nina could act to really cool the N Pacific down ready for winter 2021/22

Edited by SqueakheartLW
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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
31 minutes ago, SqueakheartLW said:

At the moment we have a weak to moderate East based La Nina and this probably is playing a big part in all the northern blocking we are seeing at the moment.

If the CFSv2 comes off then all that blocking is going to rapidly disappear before winter and it will very likely end up like last winter with another boring zonal mild washout

On the plus side a Super Nina could act to really cool the N Pacific down ready for winter 2021/22

La Nina is my main concern for this winter now, especially as GLOSEA also looks similar.  Pointless having strong northern blocking now if it's all going to go down the pan in time for winter! 

Edited by Don
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Posted
  • Location: Wath upon Dearne, Rotherham
  • Weather Preferences: Snow, severe frost, freezing fog and summer sunshine
  • Location: Wath upon Dearne, Rotherham
12 hours ago, SqueakheartLW said:

At the moment we have a weak to moderate East based La Nina and this probably is playing a big part in all the northern blocking we are seeing at the moment.

If the CFSv2 comes off then all that blocking is going to rapidly disappear before winter and it will very likely end up like last winter with another boring zonal mild washout

On the plus side a Super Nina could act to really cool the N Pacific down ready for winter 2021/22

I admire your optimism but I'm not that patient!

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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
36 minutes ago, Premier Neige said:

I admire your optimism but I'm not that patient!

Short term pain, long term gain?!  I know what you mean, winter 2021/22 is too far off! 

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Posted
  • Location: Wath upon Dearne, Rotherham
  • Weather Preferences: Snow, severe frost, freezing fog and summer sunshine
  • Location: Wath upon Dearne, Rotherham
1 hour ago, Don said:

Short term pain, long term gain?!  I know what you mean, winter 2021/22 is too far off! 

Don't get me wrong, a cold 21/22 winter would be great but after the last 2 non event winters I'm hoping for something a bit colder this year.

I do think some of the models are overcooking the strength of la nina but even the one's that do show a strong nina don't seem to have it lasting too long. (Although this graph is from September).

 

 

figure4.png

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Posted
  • Location: Lincolnshire - 15m asl
  • Weather Preferences: Frost and snow. A quiet autumn day is also good.
  • Location: Lincolnshire - 15m asl

image.thumb.png.4a6708f4fe99cd06fef64c37d8985a6a.png

v

image.thumb.png.784c32e4f5894da9d464e5b7f5812cbb.png

 

ie Oct v Sept run for 3.4. It's quite a big shift towards a strong event. Not good news for later winter cold perhaps - unless we get a shattered vortex. All these teleconnections are important....but on their own they mean little. I'd have preferred this indicator to stay at around the -1.5 mark though rather than suggest -2........

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Posted
  • Location: Heckmondwike, West Yorkshire
  • Location: Heckmondwike, West Yorkshire
4 minutes ago, Catacol said:

image.thumb.png.4a6708f4fe99cd06fef64c37d8985a6a.png

v

image.thumb.png.784c32e4f5894da9d464e5b7f5812cbb.png

 

ie Oct v Sept run for 3.4. It's quite a big shift towards a strong event. Not good news for later winter cold perhaps - unless we get a shattered vortex. All these teleconnections are important....but on their own they mean little. I'd have preferred this indicator to stay at around the -1.5 mark though rather than suggest -2........

I don't suppose you know of any cold or at least half cold UK winters that coincided with a strong Nina? 

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Posted
  • Location: Scouthead Oldham 295mASL
  • Location: Scouthead Oldham 295mASL
11 minutes ago, Catacol said:

image.thumb.png.4a6708f4fe99cd06fef64c37d8985a6a.png

v

image.thumb.png.784c32e4f5894da9d464e5b7f5812cbb.png

 

ie Oct v Sept run for 3.4. It's quite a big shift towards a strong event. Not good news for later winter cold perhaps - unless we get a shattered vortex. All these teleconnections are important....but on their own they mean little. I'd have preferred this indicator to stay at around the -1.5 mark though rather than suggest -2........

Glosea is going for a strong Nina.

I would put money on it being near the mark

 

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