Winter 2023/24 - Discussions & Forecasts

[Weather-history]

19 hours ago, Mike Poole said:

Yes, according to the NOAA compendium:

NOAA CSL: Chemistry & Climate Processes: SSWC

CSL.NOAA.GOV

---

NOAA CSL: Advancing scientific understanding of the chemical and physical processes that affect Earth's atmospheric composition and climate.

Not all SSWs are followed by UK cold, this one in Feb 2002 seemed to be followed by a +NAO, so I expect it went unnoticed.

In other news, the +IOD appears to have now peaked:

Hopefully this will limit its impact to less than 2019/20, and allow the other, positive, drivers like the eQBO to have impact.

Actually if you look at the data, there were two SSWs that winter of 2001-2002. One at the end of December 2001 besides mid February 2002

 

Just a moment...

WWW.RESEARCHGATE.NET

 

[Mike Poole]

38 minutes ago, Weather-history said:

Actually if you look at the data, there were two SSWs that winter of 2001-2002. One at the end of December 2001 besides mid February 2002

 

Just a moment...

WWW.RESEARCHGATE.NET

 

Yes, that’s why 2002 came up earlier in the thread, I was looking at winters when there were 2 SSWs!

[CryoraptorA303]

I'm liking that the PV is peaking now in November. Hopefully that means it can have an absolute car crash in December and we can get that January blast we've been waiting a decade for.

[sukayuonsensnow]

Unless we get another 2013/2014 style Winter, hopefully Mother Nature will balance out and we will end up with a drier than average Winter (otherwise we will need to build an ark). Most of the UK have already seen more than enough rain recently.

By that logic frost and fog will be a common occurrence over the Winter, not sure what that would mean for snow tbh. The only thing getting my hopes up is how early Winter has begun in Scandinavia and the other Nordic countries.

Edited October 29, 2023 by sukayuonsensnow

[CryoraptorA303]

24 minutes ago, sukayuonsensnow said:

Unless we get another 2013/2014 style Winter, hopefully Mother Nature will balance out and we will end up with a drier than average Winter (otherwise we will need to build an ark). Most of the UK have already seen more than enough rain recently.

By that logic frost and fog will be a common occurrence over the Winter, not sure what that would mean for snow tbh. The only thing getting my hopes up is how early Winter has begun in Scandinavia and the other Nordic countries.

Thinking about what November is going to look like, most of December will probably be average to wet, then January and February will be average to dry. Nino springs tend to be dry and sunny and with the atmosphere finally beginning to connect to Nino over November this effect will probably be quite back-ended. High SSTs will likely default to average or wetter than average over December (I wouldn't really get hopes up about wintry weather around Christmas this year) and then assuming the PV bombs around late December January and February will probably be subject to blocking patterns this time around and have dry periods. February is often the black sheep and goes against the overall trend of the year - February 2023 was the driest since 1990 and had strong day/night gradients, while the rest of 2023 has largely been mild to hot and wet. Conversely, last year February was wetter than average with storm Ophelia while much of 2022 was dry and hot. In 2010 February was very wet at Gatwick while the rest of 2010 would go on to be very dry, apart from, cough, a certain infamous month. I am highly suspecting a dry and sunny spring 2024, so we'll see if February will go average-wet or wetter than average.

My roadmap for this winter is currently as follows: mild and wet start to December, unsettled mid-month, a more settled spell kicks in towards Christmas and the new year. Overall December is milder and wetter than average. January is hit with heavy blocking patterns, especially later on, and ends up dry, sunny and cold. February is then very unsettled and has both dry, blocked and wet Atlantic-driven periods. Going into March things will dry up, and Spring 2024 will then be very dry and sunny, possibly the driest and/or sunniest on record, but I won't speculate that far ahead and we can wait until closer to the time. Obviously subject to change.

[Cheshire Freeze]

Couldn’t hope for a better general set up heading towards winter than what we have at present IMO.

Displaced jet stream piling deep troughing against heights to our E.

Could get very interesting later Nov and Dec IMO…

[Chesil View]

2 hours ago, Cheshire Freeze said:

Couldn’t hope for a better general set up heading towards winter than what we have at present IMO.

Displaced jet stream piling deep troughing against heights to our E.

Could get very interesting later Nov and Dec IMO…

I have to agree. CF. Happy to see that set up now with more interesting stuff from a wintry perspective further down the line.

[Mike Poole]

4 hours ago, Cheshire Freeze said:

Couldn’t hope for a better general set up heading towards winter than what we have at present IMO.

Displaced jet stream piling deep troughing against heights to our E.

Could get very interesting later Nov and Dec IMO…

Wholeheartedly agree.

This thread has been going a while now, and amidst the doom-laden prognoses of some, a few of us have held out some confidence in an interesting winter ahead right from the get go.  That idea is starting to gather momentum now.

So what if the world is record breaking hot right now, what matters more than anything for winter in the UK is are we in a zonal pattern or a blocked pattern?  If it is zonal it will be a degree or so warmer than usual for mild, with the concomitant increased wetness.  Fine.

I just don’t think that is going to happen.  One feature of this unprecedented year in weather is stuck patterns, i.e. meridional patterns, and if that persists into winter, it is half the battle won - we still have to get on the cold side of the jet, of course.

But the current patterns in the troposphere are excellent in every regard, propensity for blocking, increasing signs that that is likely to strongly influence the strat vortex into early December, jet stream well south now - the chess pieces are being moved to the right places.  And with signs (as posted by others) of a rise in AAM and that we might get assistance from favourable MJO phases (the two are related) this should, as I understand it, continue to promote a meridional component to the jet stream into winter, with power to add from a potential early strat warming in early December.  

It has been a tendency on here in recent years to give up on winter before it has started, understandable given the dross served up in the last decade, but the permutations possible are much more than one decades worth of data can give an insight to.  Let the game begin!  We hold good tickets this year…

Edited October 29, 2023 by Mike Poole

[CryoraptorA303]

49 minutes ago, Mike Poole said:

One feature of this unprecedented year in weather is stuck patterns

Typical eQBO + El Nino shenanigans. Apparently this combination leads to the most blocking out of any possible combo, which makes sense as this is logically the most disruptive to westerly movement. I am also getting the feeling that this winter will be dominated by consistent blocking; sometimes we'll be on the bad side of the block, but statistically we also eventually have to end up on the good side.

Climate change is obviously a factor, but bad weather hasn't exactly helped in the last decade. We've ended up on the short stick many times, and the long stick very few times. Climate change is making the "middle stick" a progressively worse option, and the short stick even worse than it already would be. Draw the long stick and surely we can still get something at this stage.

[Chasbrown]

Can I add my voice to those thinking that we will finally see some proper winter weather this season. It definitely feels like something is brewing, maybe wishful thinking but I don't believe so. As ever time will tell but I'm calling it now, this winter will be Dickensian! On a separate note with the possibility of violent storms this week please ensure that your home insurance is up to date. 

[CryoraptorA303]

Just now, Chasbrown said:

Can I add my voice to those thinking that we will finally see some proper winter weather this season. It definitely feels like something is brewing, maybe wishful thinking but I don't believe so. As ever time will tell but I'm calling it now, this winter will be Dickensian! On a separate note with the possibility of violent storms this week please ensure that your home insurance is up to date. 

I hope so. NA seems to have drawn quite a few long sticks lately at our expense, so hopefully it reverses this time. Generally we have the opposite of what they're having.

[Catacol]

On 28/10/2023 at 15:07, blizzard81 said:

I'm liking the latest trends at week's 3 & 4 from the cfs. Blocking becoming stronger and stronger to the north east as we approach the end of November. 

Ural/Kara High. Thaaaarrrr she blows......

[captaincroc]

Im no expert, but following the charts for over 20 years this year is definitely no normal lead up to winter.  Southerly placed Jet Stream/Lows, even when the contrast of the autumnal temps which normally fire it up. I don't know all the other players involved in what we get in weather but just from general chart watching and following patterns of summer, this winter has potential to be different. Yes we could end up in a warmer side of the jet etc but also I'd rather than risk than see deep blues and purples to our north west on the charts.

[CryoraptorA303]

2 hours ago, captaincroc said:

Im no expert, but following the charts for over 20 years this year is definitely no normal lead up to winter.  Southerly placed Jet Stream/Lows, even when the contrast of the autumnal temps which normally fire it up. I don't know all the other players involved in what we get in weather but just from general chart watching and following patterns of summer, this winter has potential to be different. Yes we could end up in a warmer side of the jet etc but also I'd rather than risk than see deep blues and purples to our north west on the charts.

With how unstable and disturbed the global weather system appears to be right now, there's a good chance we'll experience both. 2021 was the closest we got to this kind of instability, when we had quite a nice cold snap and lying snow for some days in the SE, before temperatures rapidly rose to consistent double digits the next week and the rest of February was extremely warm. I think London stations even managed to reach 18C on the warmest day. Then in March it continued and on the 30th we had the second-hottest March day on record; I'm fairly certain some places in East Anglia reached 25C and threatened the all-time record of 25.6C. I remember that day being very unexpected and unusually warm for March, certainly the hottest March day of my lifetime. And then of course temps rapidly dropped and April was more like a milder February or early March, and May was more like a cooler October. I have a feeling the first half of next year will be like this, except the colder spells will be much shorter-lived and less notable and we'll have more than one September 2023-style heatwave. I also think next spring will end up very dry and sunny overall which will be a bad start if summer 2024 then decides to start playing with heat domes. Overall very typical Nino/eQBO stuff and it will be a considerably hotter version of 2010 or 2020 (the two years you'd never suggest as analogues that actually do fit each others' profiles quite well). At least that'd mean we get something in January.

[raz.org.rain]

3 hours ago, CryoraptorA303 said:

With how unstable and disturbed the global weather system appears to be right now, there's a good chance we'll experience both. 2021 was the closest we got to this kind of instability, when we had quite a nice cold snap and lying snow for some days in the SE, before temperatures rapidly rose to consistent double digits the next week and the rest of February was extremely warm. I think London stations even managed to reach 18C on the warmest day. Then in March it continued and on the 30th we had the second-hottest March day on record; I'm fairly certain some places in East Anglia reached 25C and threatened the all-time record of 25.6C. I remember that day being very unexpected and unusually warm for March, certainly the hottest March day of my lifetime. And then of course temps rapidly dropped and April was more like a milder February or early March, and May was more like a cooler October. I have a feeling the first half of next year will be like this, except the colder spells will be much shorter-lived and less notable and we'll have more than one September 2023-style heatwave. I also think next spring will end up very dry and sunny overall which will be a bad start if summer 2024 then decides to start playing with heat domes. Overall very typical Nino/eQBO stuff and it will be a considerably hotter version of 2010 or 2020 (the two years you'd never suggest as analogues that actually do fit each others' profiles quite well). At least that'd mean we get something in January.

Next summer I'd imagine would be very hot with a lot of thunderstorms, and probably feeling tropical at times with the mix of heat and rain.

 

As for winter, I'm getting the impression that the best potential for cold will be December. I can see January and February being drier than average, going into milder than average in February.

[northwestsnow]

Metoffice update 

 

 

[summer blizzard]

Is that for Dec-Feb.

[Rain All Night]

1 hour ago, northwestsnow said:

Metoffice update 

 

 

So 0.8x the normal chance of cold is a higher chance for cold in this equivalent three-month period than we get in most years?

[SqueakheartLW]

1 hour ago, northwestsnow said:

Metoffice update 

 

 

In other words an average winter expected

[swfc]

10 minutes ago, SqueakheartLW said:

In other words an average winter expected

Its not only a fence outlook but its been creosoted

[Mike Poole]

2 hours ago, northwestsnow said:

Metoffice update 

 

 

This is a promising update, given we are still in October.  Remember that the average it is compared to is for a cooler world than now.  The context page is everything, and bodes well, particularly the bits I’ve underlined:

[Rain All Night]

1 hour ago, Mike Poole said:

This is a promising update, given we are still in October.  Remember that the average it is compared to is for a cooler world than now.  The context page is everything, and bodes well, particularly the bits I’ve underlined:

I wonder how much more favourable a set of background signals you would need to have in place at this point in the year for them to write something stronger than what they have written there...

(unless there was already a cold spell showing in the reliable near future at the point when the forecast was written, i.e. an early November cold snap)

[damianslaw]

2 hours ago, Mike Poole said:

This is a promising update, given we are still in October.  Remember that the average it is compared to is for a cooler world than now.  The context page is everything, and bodes well, particularly the bits I’ve underlined:

Reading between lines it suggests a southerly jet at times, with strong heights to the north east, battleground cyclonic conditions, with fine lines between cold and mild, the north and east exposed to greater cold.. similiar synoptics to now. Very interesting. 

[northwestsnow]

EC46 Nov 6 - 13

Temps on the ground look below average so I wouldn't be surprised if we see some frosts and perhaps a bit of wintry stuff for high ground..

Edited October 30, 2023 by northwestsnow

[Rain All Night]

2 hours ago, northwestsnow said:

EC46 Nov 6 - 13

Temps on the ground look below average so I wouldn't be surprised if we see some frosts and perhaps a bit of wintry stuff for high ground..

It also goes the whole run without showing a single positive height anomaly over Europe...

Edited October 30, 2023 by RainAllNight