Quantum
04 February 2023 12:06:20
The infamous lobe forms today, around nowish actually.

So I wonder if there could be some big swings and roundabouts on the 12Z and the 18Z as we finally get the models initialized post lobe formation.
 
Twitter: @QuantumOverlord (general), @MedicaneWatch (medicane/TC stuff)
2023/2024 Snow days (approx 850hpa temp):
29/11 (-6), 30/11 (-6), 02/12 (-5), 03/12 (-5), 04/12 (-3), 16/01 (-3), 18/01 (-8), 08/02 (-5)

Total: 8 days with snow/sleet falling.

2022/2023 Snow days (approx 850hpa temp):

18/12 (-1), 06/03 (-6), 08/03 (-8), 09/03 (-6), 10/03 (-8), 11/03 (-5), 14/03 (-6)

Total: 7 days with snow/sleet falling.

2021/2022 Snow days (approx 850hpa temp):

26/11 (-5), 27/11 (-7), 28/11 (-6), 02/12 (-6), 06/01 (-5), 07/01 (-6), 06/02 (-5), 19/02 (-5), 24/02 (-7), 30/03 (-7), 31/03 (-8), 01/04 (-8)
Total: 12 days with snow/sleet falling.
Hippydave
04 February 2023 14:15:31
Be interesting to see if the strat forecast from GFS is correct and whether it has an impact for the end of the month/early March. If it does become a SSW and it propogates I think it can bring a few days of unsettled weather as the westerlies get pushed down to the surface, even if blocking follows. (Lot's of if etc. there and if it all comes off there's still a decent chance it'll create a block in the wrong place for cold and we go very mild or get stuck under a trough). 

Uneductated strat musings aside, one interesting thing in the models is the HP being more influential - nearly a complete turnaround from an unsettled 1st week or so of the month that looked the form horse a while ago. 
 
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Work: Tonbridge
idj20
04 February 2023 16:55:11
Originally Posted by: Hippydave 

Be interesting to see if the strat forecast from GFS is correct and whether it has an impact for the end of the month/early March. If it does become a SSW and it propogates I think it can bring a few days of unsettled weather as the westerlies get pushed down to the surface, even if blocking follows. (Lot's of if etc. there and if it all comes off there's still a decent chance it'll create a block in the wrong place for cold and we go very mild or get stuck under a trough). 

Uneductated strat musings aside, one interesting thing in the models is the HP being more influential - nearly a complete turnaround from an unsettled 1st week or so of the month that looked the form horse a while ago. 
 



There does seems to be a growing trend for deepening Atlantic lows to take centre stage after Valentines Day, looks like the results of deep cold over North America turbo charging the mid-Atlantic jet stream once again. Of course plenty of room for mind changing given the time frame and hope our luck holds out with this season’s zero-named storm record.
Folkestone Harbour. 
Karl Guille
04 February 2023 19:53:10
So GFS has continued to downgrade the downgraded output for next week.  Yesterday uppers over France were still looking cold in an easterly feed at between -4 and -8 but now look more like being between 0 and -4!
St. Sampson
Guernsey
MBrothers
04 February 2023 20:26:14
Originally Posted by: The Beast from the East 

GFS 06z again teasing, but we know its utter bollox
Reading through netweather last night, you would be forgiven for thinking the dawn of a new ice age was approaching

it does get a bit historical on the other side but at least folk on there bother to post occasionally unlike here lately.
tallyho_83
05 February 2023 00:33:34
Many GEFS ENS going for reversal of zonal flow at 10hpa just after mid month now! 
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www.magical-moon.com


nsrobins
05 February 2023 08:55:02
Originally Posted by: tallyho_83 

Many GEFS ENS going for reversal of zonal flow at 10hpa just after mid month now! 

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A technical SSW may occur as modelled but we know how reliable GFS has been of late so I wouldn’t be too confident. And if it does the literature suggests only a 30% or so increase in the chance of TPV repositioning and a subsequent surface response to get cold air in our direction. I think the third week Feb with a 10 day lag is a little late to be useful anyway.
All IMHO of course, but for this winter the ship has probably already sailed now.
 
Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
The Beast from the East
05 February 2023 08:56:09
The ECM 10 day mean pretty much means game over for this winter. Even the most optimistic guys on the other channel have given up now. Good night, God bless, roll on another burning hot summer!
https://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=1&map=0&type=1&archive=0 
"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
ballamar
05 February 2023 09:19:39
Originally Posted by: The Beast from the East 

The ECM 10 day mean pretty much means game over for this winter. Even the most optimistic guys on the other channel have given up now. Good night, God bless, roll on another burning hot summer!
https://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=1&map=0&type=1&archive=0 


10 days is up to 15th Feb which is13 days before the end of winter. granted it doesn’t look good but you cannot write it off yet. Even if it is wintry weather you want March can deliver especially further north. As we have seen things can change quickly.
Hippydave
05 February 2023 10:10:28
Originally Posted by: nsrobins 

A technical SSW may occur as modelled but we know how reliable GFS has been of late so I wouldn’t be too confident. And if it does the literature suggests only a 30% or so increase in the chance of TPV repositioning and a subsequent surface response to get cold air in our direction. I think the third week Feb with a 10 day lag is a little late to be useful anyway.
All IMHO of course, but for this winter the ship has probably already sailed now.
 



I think strat forecasts are generally more reliable irrc?

Can't really disagree with the odds bit - 1/3 for it to affect surface and then circa 70% (MetO quote) for that to bring colder weather towards us. Not exactly a high chance, hence I guess why whilst SSWs are fairly common, severe cold spells for the UK aren't. 

I would though happily accept cold weather right at the end of winter into March - 2018 was pretty exceptional but showed what can happen and March 2013 was fun for a short while down here. 2005 wasn't bad either - all exceptions to the normal of course but I don't mind a bit of spring snow, particularly as when the pattern inevitably collapses you often get early spring warmth following.
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Work: Tonbridge
Jiries
05 February 2023 10:47:00
Originally Posted by: nsrobins 

A technical SSW may occur as modelled but we know how reliable GFS has been of late so I wouldn’t be too confident. And if it does the literature suggests only a 30% or so increase in the chance of TPV repositioning and a subsequent surface response to get cold air in our direction. I think the third week Feb with a 10 day lag is a little late to be useful anyway.
All IMHO of course, but for this winter the ship has probably already sailed now.
 



All the cold air being diverted to Greece to East Med instead of coming here.  Not bother with it now as this coming pleasant early Spring sunshine warmth are rapidly helping to cut heating costs much less starting from today onward.   
tallyho_83
05 February 2023 13:18:48
Originally Posted by: Jiries 

All the cold air being diverted to Greece to East Med instead of coming here.  Not bother with it now as this coming pleasant early Spring sunshine warmth are rapidly helping to cut heating costs much less starting from today onward.   



I totally agree actually - always seems to be the case and this is a re-occurring pattern as is the colder than average NW Canada/ NW USA esp early in winter.

I guess the only good thing about this winter is that we did have a little snow in December and some middle of January - not a lot but wet snow and as for the milder February well this is typical of a La Nina - similar to last February! However never say never. winter 17/18 was a La Nina and we had a cold start to winter but then in February the SSW changed things and we saw an exceptionally cold end to February lasting way into March with two BFTE's. 

I know I am clutching straws here but compare the zonal winds speed at 10hpa this year compared to what it was in red last year see below showing many GEFS members going for reversal and a month earlier than last year?

Last year we didn't see a SSW until 19th March 2022 and this brought us a cold wintry April especially 1st half with snow and a wetter May.


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Retron
05 February 2023 13:21:30
Originally Posted by: tallyho_83 



Last year we didn't see a SSW until 19th March 2022 and this brought us a cold wintry April especially 1st half with snow and a wetter May.


That was the final warming - it happens ever year, y'know!

It'll be interesting to see what tomorrow's EPS update says... it was a case of close, but no cigar on Thursday's update.

https://charts.ecmwf.int/products/extended-zonal-mean-zonal-wind?area=nh&base_time=202302020000 
 
Leysdown, north Kent
tallyho_83
05 February 2023 13:40:42
Originally Posted by: Retron 

That was the final warming - it happens ever year, y'know!

It'll be interesting to see what tomorrow's EPS update says... it was a case of close, but no cigar on Thursday's update.

https://charts.ecmwf.int/products/extended-zonal-mean-zonal-wind?area=nh&base_time=202302020000 
 



True but what I was saying is that this year we have already had a Stratospheric warming and the PV is weaker than last winter and will get an SSW (if it all plays ball) just after Mid February which was a month or so earlier than the last SSW on 19th March 2022 and that was the only warming of the stratosphere last year so there is more time in this years SSW after mid February if it comes about.

Also the SSW when we had the BFTE didn't occur until 10th February - and then all things changed end of February into March when we had two easterly spells in less than 3 weeks with sub zero daytime maxes and 7-10" of powdery dry snow. This will highly unlikely be the case this year but just shows...it can happen and has happened.

Shame the easterly spell for the south (forecasted last week) didn't materialise for this coming week - I am convinced that the Cold N/NE America /Eastern Canada has ruined things for us once again! Unless it's just a coincidence - Colder Eastern USA/E Canada - Milder NW Europe and vice versa! ETC 
Home Location - Kellands Lane, Okehampton, Devon (200m ASL)
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ballamar
05 February 2023 13:52:50
Originally Posted by: tallyho_83 

True but what I was saying is that this year we have already had a Stratospheric warming and the PV is weaker than last winter and will get an SSW (if it all plays ball) just after Mid February which was a month or so earlier than the last SSW on 19th March 2022 and that was the only warming of the stratosphere last year so there is more time in this years SSW after mid February if it comes about.

Also the SSW when we had the BFTE didn't occur until 10th February - and then all things changed end of February into March when we had two easterly spells in less than 3 weeks with sub zero daytime maxes and 7-10" of powdery dry snow. This will highly unlikely be the case this year but just shows...it can happen and has happened.

Shame the easterly spell for the south (forecasted last week) didn't materialise for this coming week - I am convinced that the Cold N/NE America /Eastern Canada has ruined things for us once again! Unless it's just a coincidence - Colder Eastern USA/E Canada - Milder NW Europe and vice versa! ETC 


Tally be careful stating it was forecasted, was a small chance less than 15%! It was great to see in a small number of perts and some of them showed great potential but it was never any more than a small chance. That’s what the thread is about seeing if we can spot something before others - I hope you didn’t tell anyone
UncleAlbert
05 February 2023 14:51:52
Originally Posted by: ballamar 

Tally be careful stating it was forecasted, was a small chance less than 15%! It was great to see in a small number of perts and some of them showed great potential but it was never any more than a small chance. That’s what the thread is about seeing if we can spot something before others - I hope you didn’t tell anyone



Yes only a low probability, but the interesting point in this case was that the GFS Op stubbornly agreed with that pert minority for quite a number of runs.  May have been a major coincidence, but  I would have thought that occurrences of this nature would be an issue for investigation by NCEP.
ballamar
05 February 2023 17:01:52
Back to the reliable GFS at the outer reaches blocking looks fairly massive and it could indicate a colder spell last week of Feb. Would fit in with recent colder spells
Rob K
05 February 2023 17:40:52
Originally Posted by: UncleAlbert 

Yes only a low probability, but the interesting point in this case was that the GFS Op stubbornly agreed with that pert minority for quite a number of runs.  May have been a major coincidence, but  I would have thought that occurrences of this nature would be an issue for investigation by NCEP.


I very much doubt that it was more than the usual variation. We only noticed it because a shift of a few hundred miles in an anticyclone made a lot of difference to UK weather. 

i’m sure it happens all the time, just not in locations we are focusing on. And I’m equally sure the GFS boffins aren’t too worried about what the model is showing for a little island on the other side of the Atlantic. 
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
Jacee
05 February 2023 19:23:51
It will be nice to see some frosts again for the coming week. One issue I had with last week was the lack of variation with the temperatures locally. A bit above average by day and above average overnight with a lot of cloud from the weakening weather fronts. A real snoozefest!

Now that scenario may return midweek as the high eases south, but for the coming few days it does look pleasant with the clearer days and frosty nights 😊

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Jacee, Hucknall (Notts) 😽 x
Spring Sun Winter Dread
05 February 2023 20:01:36
I'm already concerned at the lack of rain. IMBY the autumn offered some relief after the bone dry spring and we had a wet first half of Jan but now here we are at the start of Feb and there has been barely a drop in 3 weeks with none forecast for the week ahead.
Can already hear the "2 dry winters and a dry summer back to back " story being prepared by the water companies



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