Winter 2022-23 : Forecasts and Discussions

[Blessed Weather]

As we head through the last days of November and towards the start of winter proper, a new thread to capture and discuss the latest Winter Forecasts and thoughts on the upcoming season.

If I may ask, if your post is just a moan about the outlook then please head over to the Autumn Moans & Chat thread. Note we’ll be starting a Winter Moans & Chat thread ready for 1st December.

To help continuity between the Winter Early Thoughts thread and this thread please feel free to re-post any seasonal outlooks you've previously made from the likes of Met Office Glosea, ECMWF Seasonal, etc..

Here's a few links that you may find useful:

• Copernicus Seasonal Models (x9 models incl. ECM, MetO, NCEP, Meteo-France, JMA, etc..)
   
• Netweather Preliminary thoughts for 2022/23 Winter (Full forecast coming in the next week or so).
   
• Met Office Contingency Planner 3 Month Outlook
   
• Severe Weather Europe Winter 2022/23 Forecast
   
• US Winter Outlook (dated Oct 2022)
   
• Finally, if you’d like to know more about seasonal forecasts have a look at this link:
• Met Office Seasonal Forecasts and Climate Drivers Resources (including a video about how they produce seasonal forecasts)

As always, please keep discussions friendly and respectful. Here's to a winter full of weather interest, whatever your preferences.
 

Edited December 30, 2022 by Blessed Weather

[damianslaw]

Thanks for this. Will give my thoughts for what they are worth later in November.

I'm interested in how we seem to have a ENSO disconnect, atompshere isn't behaving La Nina like combined with it being a third La Nina winter - east based, could mean a winter that doesn't stick to the rule book - which seems an emerging theme recently, teleconnections really are being thrown into chaos. The summer caught me out - didn't expect it to be so hot and dry.

[Mike Poole]

Just to follow up on the discussion of the GloSea6 November update from the earlier thread.  The UKMO monthly charts are now available via copernicus, and are as follows for Dec, Jan and Feb:

So December a good signal for blocking to our NW, February has a strong +NAO/+AO signal.  January is in between, and it is really easy to see how the 3 month average of these looked poor, with Dec and Feb so opposite in our neck of the woods.

[damianslaw]

4 minutes ago, Mike Poole said:

Just to follow up on the discussion of the GloSea6 November update from the earlier thread.  The UKMO monthly charts are now available via copernicus, and are as follows for Dec, Jan and Feb:

So December a good signal for blocking to our NW, February has a strong +NAO/+AO signal.  January is in between, and it is really easy to see how the 3 month average of these looked poor, with Dec and Feb so opposite in our neck of the woods.

Jan looks cold. Where is the low pressure? Sign possibly to our west mid atlantic, but overall cold possibly very cold.

[Mike Poole]

14 minutes ago, damianslaw said:

Jan looks cold. Where is the low pressure? Sign possibly to our west mid atlantic, but overall cold possibly very cold.

The surface pressure plot for December suggests so:

I had remarked on a couple of the cluster plots recently about the lack of an Azores high.

[Cheshire Freeze]

41 minutes ago, damianslaw said:

Jan looks cold. Where is the low pressure? Sign possibly to our west mid atlantic, but overall cold possibly very cold.

Aye, possibly UK HP territory, which could see some very cold days if there's still snow on the ground from any snowfalls in December (entirely possible given we'll be at min solar input).

[MattH]

These plots may have been dropped in somewhere else but as, yet I've not seen these, but worth sharing the Nov C3S seasonal output for Dec and then Feb. What these plots highlight perfectly is how the 3-month mean plots can really mask monthly variations and clearly, we can get even more variation within a monthly period as well. Caution is always recommended with taking 3-month seasonal plots 'as is' and one must always try and view monthly plots or at least analyse other variables as welll.

The standout feature here for Dec is the continued signal for blocking patterns, a consistent signal for months. Will the key +ve MSLP anom end up exactly there?...clearly nobody knows, but it is the -ve NAO signature that remains very interesting indeed. In contrast and as has been expected for a similar length of time is the +ve NAO pattern for later in the winter. The primary caveat here, however, is the SSW risk which I do honestly think is higher than some may suggest within a wQBO/Nina regime, but as ever time will tell on that.

All in all it provides significant interest for the early winter period when, usually, more significant cold weather is often more realistic than compared with later in the winter, without some sort of significant stratospheric assistance/disruption.

Regards, Matt.

NB: These plots were grabbed from the Copernicus front page, not the main area where the plots are as they are still 3-monthly means. Future updates from Copernicus are set to incorporate monthly plots as well as the 3-month means which will be a great addition to the site.

 

Edited November 15, 2022 by MattH

[iceman1991]

Might sound like stupid question but has the GloSea6 new update come out for November and is it still going for the same cold start early winter as did October update ? 

[Mike Poole]

5 hours ago, iceman1991 said:

Might sound like stupid question but has the GloSea6 new update come out for November and is it still going for the same cold start early winter as did October update ? 

My take on the coming winter has been (since September) that it would be a winter of two halves, the first half offering opportunities for cold via blocking with a weak polar vortex, and a -NAO, the second half - following a coupling between the strat and trop vortexes (and assuming no SSW) - zonal and Atlantic dominated +NAO, therefore mild.

The November update to GloSea 6 supports that view, as did the October one.  Other seasonal models support it too.  And the current discussions in the MOD about the strength and longevity of the now recently established block also offer the chance of that colder start to winter.  

[iceman1991]

32 minutes ago, Mike Poole said:

My take on the coming winter has been (since September) that it would be a winter of two halves, the first half offering opportunities for cold via blocking with a weak polar vortex, and a -NAO, the second half - following a coupling between the strat and trop vortexes (and assuming no SSW) - zonal and Atlantic dominated +NAO, therefore mild.

The November update to GloSea 6 supports that view, as did the October one.  Other seasonal models support it too.  And the current discussions in the MOD about the strength and longevity of the now recently established block also offer the chance of that colder start to winter.  

Thanks for that Mike appreciate it that’s hope for the cold weather first half

[Met4Cast]

Personally.. 

I'm expecting an exceptionally mild winter this year, if not in the top 5 of mildest on record then certainly within the top 10. December holds some promise of blocking based on the seasonal models but as November progresses and we see how the SPV is developing over Greenland then i'm increasingly beginning to doubt the chances of sufficiently prolonged cold/below average temperatures. 

[jules216]

My analogs are not showing anything settled fór UK in December. Watch for UKMo changing the wording from high pressure to "unsettled". You Can already see pattern something like this developing next week,even ahead of schedule.

[Weather-history]

2 minutes ago, jules216 said:

My analogs are not showing anything settled fór UK in December. Watch for UKMo changing the wording from high pressure to "unsettled". You Can already see pattern something like this developing next week,even ahead of schedule.

I find the years given below in these charts baffling at times. I'm assuming they are for similar  past Decembers?

Dec 1999, 2008, 2013, 2000, 2020

Really December 2008? I recall a bit of high pressure certainly during the last week of that month, I wouldn't have thought the 500mb anomaly would have been that intense.  

[Blessed Weather]

I wonder if we dare hope that the MJO might provide some impetus for blocking to our NW during December? This week's expert analysis (on Monday 14th) struck a positive note about the evolution over the next few weeks [my comments in brackets]:

Good agreement exists among the dynamical models favoring a renewed MJO activity over the Maritime Continent [Phases 4, 5] during week-1 and propagating eastward to the Western Pacific [Phases 5, 6] during week-2, with several ensemble members indicating a potential high amplitude event. Although the ECWMF is less supportive of coherent MJO activity persisting into week-3, other extended range model solutions maintain a well organized signal over the Western Pacific and Western Hemisphere [Phases 7, 8] heading into December.

Source: https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjoupdate.pdf

Today's forecasts from both NCPE and ECMF show the MJO moving into Phase 7 around the 22nd to 25th of November:

NCPE  ECMF 

Add the typical 10 day lag for impact to manifest itself in our neck of the wood and you get to around the 2nd to 5th of December. Now I admit I'm stretching things here, but it just so happens this morning's GFS 06z forecast ended on 2nd Dec with a reasonable match to the 500 anomaly composite for MJO Phase 7 in Dec in a Nina year (MJO composite rotated to match GFS output):

GFS 06z  Ph 7 composite

Source: https://www.meteonetwork.it/models/mjo/

Just saying....... 

[Don]

9 hours ago, Met4Cast said:

Personally.. 

I'm expecting an exceptionally mild winter this year, if not in the top 5 of mildest on record then certainly within the top 10. December holds some promise of blocking based on the seasonal models but as November progresses and we see how the SPV is developing over Greenland then i'm increasingly beginning to doubt the chances of sufficiently prolonged cold/below average temperatures. 

Over to 2023/24 then!! 

5 hours ago, jules216 said:

My analogs are not showing anything settled fór UK in December. Watch for UKMo changing the wording from high pressure to "unsettled". You Can already see pattern something like this developing next week,even ahead of schedule.

Oh well, that's it then for winter!!

[damianslaw]

41 minutes ago, Don said:

Over to 2023/24 then!! 

Oh well, that's it then for winter!!

No winter's over posts until winter starts at least! There will be a winter moan thread on 1 Dec, which I will be staying well clear of.

[Kirkcaldy Weather]

2010 certainly is an interesting similar analog, you can think that's an absurd comparison if you like but clearly recent and current patterns have been similar. Also a few posts I put in the other winter thread showed that cold North / Northeast US AND UK.... 

 

 

[damianslaw]

4 minutes ago, Kirkcaldy Weather said:

2010 certainly is an interesting similar analog, you can think that's an absurd comparison if you like but clearly recent and current patterns have been similar. Also a few posts I put in the other winter thread showed that cold North / Northeast US AND UK.... 

 

 

2010 and 1995 repeat would be something special but highly unlikely, mind 1995 took until 5 Dec to get going from an easterly, so not out of the question - some similiarities with GFS later output and the synoptics of late Nov, high pressure built in from the south and merged with heights to the east in early Dec.

2017 brought a cold first 12 days or so to Dec, lots of frosty weather, bit of snow, but the Nov was quite different so far to this one, lots of northerly influence. 

[Blessed Weather]

AER Arctic Oscillation/Polar Vortex blog 16th Nov:

Dr. Judah Cohen has commenced his winter season weekly blogs with his thoughts on how leading drivers of NH winter weather are developing. Here’s my pick of a few of his comments this week:

In my opinion lots of mixed and conflicting signals about the upcoming winter.  Seems that the winter forecast is never easy, and this winter is certainly no exception and if anything seems to be even more challenging.

… the feature that needs the closest monitoring are the developing cold temperatures across Siberia in early December. The winter could very well be tethered to how long that feature can persist. The cold will persist as long as high latitude blocking persists in the North Atlantic sector but especially in the Scandinavian/Urals/Barents-Kara seas region. For what it is worth, the CFS predicts that it will be a prominent feature in December…..

One trend that I am watching is the drainage of positive geopotential heights from the Urals/Barents-Kara Seas region over towards Greenland.  This trend was already apparent in Monday’s forecast plots but has grown stronger the past two days…… the risk of colder weather to Northern Europe is increasing for early December….

GEFS 11-15 Day Forecast 500 Anomaly Forecast ending 1st December:

But as Dr. Cohen notes, developments for December could go either way:

Will high latitude blocking in the North Atlantic sector be of sufficient amplitude and duration to disrupt the PV either in the form of stretching or as a sudden stratospheric warming that creates a positive feedback loop that then reinforces high latitude blocking regionally or pan-Arctic that favors Arctic outbreaks into the mid-latitudes?  Or will a strengthening PV start to dissipate the high latitude blocking creating a more zonal flow across the Northern Hemisphere that floods the continents will relatively mild air?  And these days when it turns mild it’s not just simply mild, it’s record mild. 

Full blog: https://www.aer.com/science-research/climate-weather/arctic-oscillation/

[Summer8906]

16 hours ago, Don said:

Over to 2023/24 then!! 

Oh well, that's it then for winter!!

Or spring 2023. I'm sure spring will be nice at times, as it always is. 

Winter is just a dead loss most years. By contrast, I'd be prepared to place a bet on at least one of Mar-Apr-May being very dry and sunny. Perhaps May this time, as we've had a couple of fairly poor ones.

[Summer8906]

What's worrying me is that the GFS persists the cyclonic weather into early Dec, any suggestion of high pressure (which was shown a couple of days ago) seems to have disappeared.

Of all the analogues I can see similarities to 2000. That year Nov was extremely wet and this persisted until mid-Dec, when it became much drier and colder. Rest of the winter was a battleground between mild and extremely wet, and cold and dry. Perhaps that gives some hope for Jan and Feb being better than the horror show of Nov and perhaps early Dec?

But the suggestions of Jan/Feb zonality don't sound good either. I can just see the current low-jetstream cyclonic spell abating sometime in Dec, then the briefest anticyclonic spell, before raging zonality takes over...

Edited November 17, 2022 by Summer8906

[Skullzrulerz]

19 hours ago, Don said:

Oh well, that's it then for winter!!

Not necessarily, the reality is that The 2010 Winter was a exceptionally rare event.

People expecting something like that this year are going to be a very disappointed.

Our Climate is changing to a more warmer and wetter here in this country, that's not to say that they won't be cold winters but it's going to be incredibly rare at this rate.

[Don]

4 hours ago, Skullzrulerz said:

Not necessarily, the reality is that The 2010 Winter was a exceptionally rare event.

People expecting something like that this year are going to be a very disappointed.

Our Climate is changing to a more warmer and wetter here in this country, that's not to say that they won't be cold winters but it's going to be incredibly rare at this rate.

Don't think anyone was suggesting a 2010 redux this year?!  My initial thoughts was perhaps something similar to 2000/01 or 2020/21, not overly cold winters but certainly not without interest!  However, I now feel something similar to 2019/20 or last winter is more likely.

[Don]

23 hours ago, damianslaw said:

No winter's over posts until winter starts at least! There will be a winter moan thread on 1 Dec, which I will be staying well clear of.

Don't blame you at all, but I fear the moan thread will be rather busy!!

[Uncertainty]

50 minutes ago, Don said:

Don't think anyone was suggesting a 2010 redux this year?!  My initial thoughts was perhaps something similar to 2000/01 or 2020/21, not overly cold winters but certainly not without interest!  However, I now feel something similar to 2019/20 or last winter is more likely.

2019/20! What on earth is suggesting that Don? Unsettled weather in November? C’mon pal: Not one of the seasonals has that signal, and they all had it at this point that winter. I’d say a 16/17 winter is plausible, and of course the nightmare scenario winter is always possible, but there’s no evidence for that right now.