Winter Review

[Catacol]

Not sure it is my place to start this thread, but as we hit the half way point in March realistic winter options are behind us and, before I say goodbye for a few months (though if we get some major thunderstorm activity I might be tempted back) I wanted to quick review of the season just gone. Others chuck in your thoughts as we go.

I'd rate the season about a 6/10. We started cold - but relatively dry for most, and ended with some snowy flurries (a lot more in favoured spots) but we didn't get nationwide cold and snow for 3 or more days and so I can't lift my gut score to a 7 or more. We saw a displaced vortex at the end, a bottom up split of sorts at the start and for the most part we have not been hammered by rain and flooding. So.... a decent 6/10 and on Friday I saw snow for 2 hours so I got a bit of a fix. 🙂

In terms of forecasting review, a few thoughts:

1. MJO matching was rather good this year. We had 3 cycles through the maritimes that arrived in the western Pacific - late November, early January and then late February. Periodicity af around 45 days which is average, reasonable amplitude and on each occasion within 10-15 days of emergence into Phase 7/8 we had a -NAO blocking signal emerge as per a paper I flagged a couple of times through the season. It is a blunt tool, but as tools go the lagged impacts of MJO progress into the western Pacific has shown itself to be a pretty good indicator of high lat blocking that can set up a cold flow for the UK.

2. I think we can say we had two vortex events this year. The early season split, driven by the robust Pacific signal, gave birth to that early season cold. We had a fairly dramatic tropospheric split and sufficient cold to give us the coldest December spell since 2010. We didnt get lucky with snow amounts, but that bottom up split was significant. Late season we then got the displaced vortex that fell kindly enough to allow a 3 - 5 day spell of renewed northern cold with a bit more snow attached. Displaced not as good as a 2018 split - but it delivered. Those who do not take notice of vortex shape are missing a trick. These are forecastible events that definitely increase the chances of UK cold.

3. And what of disappointment? I have not nailed the significance of Pacific jet activity yet. Personal target to get better at it because it is something others (like Masiello) make great use of and have a proper understanding of. There is my EBI for the close season. The biggest disappointment was not seeing the promising early season context progress into a major SSW in January. I think we were not far from it, but we did not have a favourable QBO signature that statistically makes an SSW harder, and to my eye we didn't see enough solid Ural High activity pairing up with the Aleutian Low. That north pacific pattern worked out better than I had expected in a Nina season - but without the pairing we didnt get sufficient wave 2 activity. As a result chances of a Scandy High kept coming and going, and that continental easterly was elusive. But we got close - the forecasting was interesting and the fact that the Feb SSW occurred as it did, when wave activity really wasn't very high, suggests that more damage was done in January than might have appeared to be the case. Certainly we didn't end up with a raging Atlantic pattern driven by strong coupling, so that was good.

And so - 6/10. Next year an eQBO and Nino combo possibly sets us up for more robust pacific driven impacts on the vortex and a generally more active MJO (though it was pretty active this year to be fair) and that might increase the chances of the "big" year appearing in 2023/24. Who knows. Solar probably not in the right zone - active sun encourages active jet as a very simple equation - but these days I'm less concerned by solar impacts than I once was.

So - onwards to Spring and Summer. I pray we can avoid 40 degrees. I fear Nino and CC and volcanic lagged water vapour impacts might combine to create weather records once again this summer of the type I hate....but come October I'll be back. Once a snow hunter, always a snow hunter!

Edited Wednesday at 13:37 by Catacol

[Chesil View]

A great review Catacol.

I'd give it a six as well.

Nothing truly outstanding in terms of snowfall outwith the time of year and location parameters. This most notably shown my locale in the recent transient snow event where the north Dorset Hills caught a covering for a day or so.  Which is absolutely bog standard stuff.

The December cold was notable and as some have pointed out the most nota left since Dec 2010 but again snowfall was still relatively regionalism. 

The recent March  burst saw the usual suspects get the bulk of very heavy and lying snow.

Proving that in terms of lowland southern England we really do need exceptional circumstances a la 2018 2010 etc to provide deep lo glassing snowcover in these (climate) changed times.

[Sunny76]

3 hours ago, Chesil View said:

A great review Catacol.

I'd give it a six as well.

Nothing truly outstanding in terms of snowfall outwith the time of year and location parameters. This most notably shown my locale in the recent transient snow event where the north Dorset Hills caught a covering for a day or so.  Which is absolutely bog standard stuff.

The December cold was notable and as some have pointed out the most nota left since Dec 2010 but again snowfall was still relatively regionalism. 

The recent March  burst saw the usual suspects get the bulk of very heavy and lying snow.

Proving that in terms of lowland southern England we really do need exceptional circumstances a la 2018 2010 etc to provide deep lo glassing snowcover in these (climate) changed times.

Even in the so called classic era up to 1987, we had years without any snow in the south.

Between 1979-1991, we only recorded heavy snow in London in 1981/82, January 1987 and February 1991, with snow flurries in February 1983 and some light snow in early 1985.

80,81,84 and 86 were pretty useless. 

[Don]

On 15/03/2023 at 20:01, Sunny76 said:

Even in the so called classic era up to 1987, we had years without any snow in the south.

Between 1979-1991, we only recorded heavy snow in London in 1981/82, January 1987 and February 1991, with snow flurries in February 1983 and some light snow in early 1985.

80,81,84 and 86 were pretty useless. 

Jan/Feb 1985 were snowy months in the south east and February 1986 wasn't too shabby either.

[damianslaw]

Yes I'll agree with a 6/10 - this also includes March up to now, the cut off being today, without the recent snowy spell it would be a 5/10. 

The 7-17 Dec was excellent for early sustained cold, not as potent as 2010 but not far off, snowfall wise disappointing here, shame because had any appreciable snow fell on the 9th/10th rather than the 2cms we had, it would have stuck on the ground for over a week to give a winter wonderland scene. Alas, we had 4 ice days between the 12th and 15th. 

Mid Jan delivered a bit more snow and more cold weather but nothing significant but it at least felt like mid winter on the back of the sustained very mild and wet spell we had endured since the 18th Dec.

A big positive is the weathe rmade for few headlines this winter. No flooding or storms here.

Most dissapointing elements, the cold relenting just in time for christmas - yet again another mild wet run into christmas, 11th year in a row this had happened, Another wet mild gloom festive period. 

February as a whole - what an uninteresting month, no snow, a bit of frost and just bland nothingness.

A better winter for cold than 13-14, 14-15, 15-16, 16-17, 18-19, 19-20 and 21-22 so on this front preety decent, but the cold was rather fleeting and cancelled out by anomoulous mild.

Snowfall wise, better than 13-14, 15-16, 16-17, 18-19, 19-20 and 21-22, on a par with 14-15, but quite a bit behind 12-13, 17-18 and 20-21. The fells in particular have been snow barren for lengthy periods - the cold periods cut short with abrupt change to mild, and due to lack of much snow, a quick thaw took place on each occasion.

Here's to winter 23-24 and if we see a notably cold snowy one, hopefully the country will be in a better place to cope than the last 3 winters.

 

He

[stewfox]

7 out of 10 for me. 3 decent cold snaps in Dec,Jan and March. Snow in Dec and March

Beats some winters with lamp post watching  for flakes of  snow at 2am in some winters of the 1990s,I think it 4am.

 

[January Snowstorm]

4/10 for my location. We do well from Polar Northwesterlys and of course we had none this season. I saw a couple of hours of falling snow and no lying snow (the first time in quite a few years we didn't even see a day of lying snow) I agree though the pre Christmas cold was quite something and from a cold/frost pov was well up there. For that alone it deserves a few points.

From a weather enthusiast view it was very boring though with not even one named storm. Noteworthy in a different way..

Also a dent in confidence on how Strat warmings pan out. We seemed to get a major event that in all honesty lead to very little on the ground! It's not the be all and end all & I think we were reminded of just that.

Edited yesterday at 21:54 by January Snowstorm

[damianslaw]

10 minutes ago, January Snowstorm said:

4/10 for my location. We do well from Polar Northwesterlys and of course we had none this season. I saw a couple of hours of falling snow and no lying snow (the first time in quite a few years we didn't even see a day of lying snow) I agree though the pre Christmas cold was quite something and from a cold/frost pov was well up there. For that alone it deserves a few points.

From a weather enthusiast view it was very boring though with not even one named storm. Noteworthy in a different way..

Also a dent in confidence on how Strat warmings pan out. We seemed to get a major event that in all honesty lead to very little on the ground! It's not the be all and end all & I think we were reminded of just that.

SSW events are hit and miss, I think splits are better for cold prospects than displacements, think 12-13, 08-09 and 17-18 which were splits I think??? 2020-21 was a displacement possibly? 19-20 a displacement that had no affect whatsoever.

[hillbilly]

A notable cold spell in December but little snow until the brief few days in March ,better than many years in modern times but by 80s standards  a disapointing showing,average frost days.

[Ross90]

Lacking windy days too, just one yellow warning for wind since the autumn which is quite unusual up here. There hasn't been an Amber warning in over 3 years now.

[al78]

A very benign winter consisting largely of nothing weather. Notably lacking in windstorms. The dry February was a surprise and in some ways welcome as it meant I don't get wet everytime I set foot outdoors, although March seems to be dishing out the punishment weather now. Some good cold seasonal weather at times but no snow (the only lying snow here being a couple of weeks ago and only for a few hours).

[johncam]

4/10 for me ,had two mornings with slush ,one of the  worst that I can remember 

[cheeky_monkey]

for my location thus far its been a 7/10..here the less cold and snow the better the opposite of what most want in the UK ..apart from the 2 very cold spells at the beginning of Dec and Just before Xmas its been pretty average temperature wise..Dec was quite snowy but there has been little in the way of snow since Xmas ..a good benchmark for winter is walking conditions (as i walk 10 miles a day every day) i have not had to wear any ice spikes on my footwear this year ..which means its not been icy and slippy out.. this is due to little in the way of Mild spells which causes any thawing and lying water to refreeze rapidly ..not quite as good as 2020-21 but way better than last year which was an icy mess.

[damianslaw]

The lengthy dry spells this winter, first half of Dec, mid Jan to end Feb, combined with lack of anything stormy, or especially wet, and a lot of sunshine has made for a short feeling winter this year. Certainly been spared much in the way of drab dull anticyclonic weather, or constant washout cloud filled south westerlies, though mid Dec to mid Jan did bring such conditions. The very calm February perhaps the most unusual aspect of the winter, whilst it can be very dry, rarely it is so calm as well.  Its made for a winter devoid of anything really troublesome, not many weekends runied by the weather, I remember the start of 2020 when our walking club had to cancel 5 weekend walks in a row due to wind and rain.

[matt111]

I'd give it a 4/10 here. The only real interest was the colder temperatures we had on a few days/nights which were quite impressive for here but to not see any snow at all from that impressive cold apart from a couple of minutes of back edge snow was a real disappointment. Otherwise it was a winter devoid of anything remotely interesting with no snow, no storms, no real windy weather at all and lengthy spells of often cloudy  nothingness. Not a winter that will live long in the memory that's for sure, and it joins a number of recent forgettable winters. 

[Norrance]

 I will go for 4 out if 10 too. Only two half decent snowfalls, both in December and the second came with the breakdown so didn't last long. The cold spells in January and March were pretty much dry with only a light flurry or two and again a little snow with the breakdown in the latter. Northerlies don't often do it for here with the Cairngorms in the way.