jules216

In general its an "averaged out" process like example La Nina has no effect on European winter yet some did yield -2 anomalies,others did +2. This event however is textbook stuff as in our Slovakian experience -NAO doesnt mean cold generally and this event will also bypass cold 500km to NW from us. The holly grail is EAP- east Atlantic pattern where high pressure sits like in 2016-17 winter. -NAO is high risk high reward stuff about 70% of time ends in rain with short but very mild periods followed by cooler weather when -NAO breaks Down thats when everything takes aj eastward motion - 2009,2010 or 1996. However very nasty outcome is December 2020, February 2009 or short period of west based -NAO around Christmas last year.

Mika Rantanen on Twitter has a good point how -NAO has been resulting in much less severe outcome for Northern Europe because Arctic has been warming so much, this being 80s would yield 1°C instead of 4°C for you in UK. but no event is the same, however trends are there. That is why we need an easterly instead! Meanwhile finally some frost this morning.

Who knows whats to blame, maybe that stupid +AMO atracting low pressure in worst places in Atlantic forcing/dragging patterns too far west.

There comes that "Romanian" high pressure imagine -5 NAO yet only -4 uppers coldest at 90% of Continental Europe, nonetherles this was flagged by analogs, luckily what analogs are also saying trough will have tendency to migrate east in January. Also Masiello on Twitter hinting at January reload of -NAO, this is textbook stuff and exactly a trend seen on the analogs. December always a bit of a bonus if we catch some cold but 90% of time its what Can go wrong does. Here with perhaps one exception being 2012 in past 10 years.

Yes broken clock right 2xdaily too. The dry theme was on 16-30 dayer for over a month now kept pushed back. End result 124mm rain in London for November double the usual amount. There is very little excuse for the seasonals both EC and UKMO that had a very dry november look.

Here is zoom in on Európe analogs vs EC this morning. To me this aint a 1995,2010 scenario but a blend od 2000,2020 neither it is unfortunatelly a 1984 scenario either. Might be good/ok for the most western parts of Europe.

And to follow Up on my above comment, I ve isolated combined blend of analogs vs the ECMWF 0Z "outcome" a touch more -NAO this year courtesy of Nino regime we been in otherwise its a Mirror image. I ve been also pointing out a lot how misserable the UKMO 16-30 day was with constant dry theme clearly a big fail.

For me ECMWF op was a joke about +5 degree outlier. See bottom row. But sometimes its a trend setter as its run on Higher resolution as also control day 10-15 was mediocre ending in +5 night time temperature which I presume meant not even high pressure but trough somewhere around south Alps, regardless of today I personally believe we are heading fór 2020/21 redux as axactly what I wrote in my winter forecast from 08.10.2022

I am on the easterly trough with -5 uppers at the moment for last few days an my temperature oscilates between +4/+3 no amplitudes,no frost,no sun no Snow. And I am on 370m.asl. just saying for you that maybe later you Can get similar spell of weather as I see -5 uppers probably coldest scenario for UK. I would rather have a westerly with sunshine and showers then this.

What did I say few days back, there is a long way back to cold from west based -NAO for most of Europe. Because its a presursor to pumping high pressure ahead of low that dives just to west of Ireland, how are you gonna get that low to travel 3000km east to pull northerlies rather then southerlies?

I had a look in to past of historical SSW and for central Europe more often the presursor pattern is colder then after SSW,there is usually a more coherent push of cold about 30-60 days after. Example January 1987. Ssw after freeze,then very cold March. Its west Europe that benefits most from split SSW sa sadly the "Romanian" high post Haddley Cell expansion is that cruicaly 5N more northward.

Sadly, and more sadly Europe hasnt seen a deep freeze setup since 02/12 with perhaps exception of January 2017 and very end of feb 18! And it certainly isnt because of "lack od trying" I dont write down failed attempts but from every year experience ať least 3-4 spells slipped away "last minute" this is not concerning UK only but more widespread regions.

Mostly a combination of west based -NAO and "Romanian high/Portuguese low" exactly what I said before!

Its not that I would make you believe its not happening anymore, but evidence is there around the start of December a possible cold spell has slipped away because that "Rimanian" high. Not to forget last week easterly where cold from Belarus took a "last minute" northward track flooding Poland and parts of Czechia with cold and snow but northerly track meant potential blocking got mixed out and high pressure there again to the rescue from south. Its just a begining and already 2 ocasions the potential slipped away,now we are looking at possibly something after 10.12. dont forget Tamaras words we wont be riding this Ninoesque AAM blocking forever. Also prospects of temporal -NAO(could turn out to be west based) and we are loosing Ural high and heat flux. Remember Christmas 2021 turned out to be west based -NAO then we lost Pressure on stratosphere. So there is a big risk of "fruitless Scural high retrogressing to west based -NAO and no more pulses of strat warming cemented by destructive interference of Nina when it matters most. Tíme will tell.

You see and yet my comments come across as pesimistic but I have been proven right many times. Why not even consider those ideas? Some experienced people do agree with me on the fact caution is required. My seasonal analogs since spring this year have Also Been spot on! Check Twitter.

I was doing my winter analogs on the 08.10.2022 and here how they stack Up against latest GEFs trends. I have explicitly mentioned "unlucky" outcome for Slovakia and blocked Atlantic, so far its going accordingly.

I also mentioned in earlier post about a threat of WB -NAO and "All of the sudden" here is latest GFS anomally, there is also that Portuguese trough doing no one any favors. Its just plain ridiculous to have a lovely Scandi blocking transfering to -NAO but not east based, what has happened to Europe since 2011-12 February that every possible cold spell gets scuppered by something.

Cut off low Portugal pumping high pressure in to central Europe and easterly for Turkey. Just as I said before morning run.

But you Can already see corrections that easterly is beigh cut off on this morning ECMWF as exactly how i pointed out! Small trough France/Portugal only serve to delay proper easterly, how come no one else talking about this just pure -NAO fixation.

Never seen so much hype when ensemble mean is showing -2 uppers, what is clear to an unbiast viewer there are 2 issues. 1. Trough that slides down to Portugal pushing ahead high pressure from Greece-Turkey to central/east Europe cutting of Easterly pronto. 2.Attempt at -NAO later engages Scandi trough with Portuguese one forcing west based -NAO later putting America in to freezer yet again!

Models offer some building blocks with many hurdles to overcome, one in my views because I also look east not just at NAO is high pressure around Turkey that has a tendency to nudge nortward and cut of the really cold easterly. Icon 12Z does bring some -4 uppers untill 144hr, thats enough for 800m+ altitudes. One example today here at my area in Slovakia we are under slow filling trough in NW flow and -3 uppers, outside temperature is +4.1 and miserable rain and I am at 400m.asl. It is the absolute worst case scenario in my view. This autumn from 85 nights there were only 3 clear skies, I dont remember worse autumn ever, very warm uppers in October came too late and only gave endless low cloud weather. Going forward these anomalous mediocre 550dam geopotential under -4 uppers are forecast to have interval of +5/-1 - more misery. Winters here have turned in to a 3 month wait until spring,nothing else.

Few days on and All of the sudden high pressure from Greece comes to the rescue, from potential cold easterly comes +3 uppers mid range forecast. All the potential winter charts remain over 240hr+

A few daily records broken in Czechia this morning. Station Orlicke Záhorí -17,5°C. Looks like typical weather over here where any rare cold spell bypasses Slovakia to the north by 200km where Poland and Czechia gets hammered by snow, then a la carte next night clear. Had to put up with this all winter 2020/21. Waiting for the next week debacle where advecting high pressure will have a trough sitting somewhere in Germany so their Alps,Austria and Once again Czechia get hammered while I be pulling a south easterly and rain under 3°C like who days ago. This happend on and off All winter 2020/21, no wonder because that winter is a very good analog anyway.

Looking at latest developments things are progressing nicely towards the turn of the months to resemble blend of my winter analogs for december. Deep trough near UK/IE and east Europe high. Had a look at heat map fór EPS and it already suggest a warm up here in Slovakia days 12-15 from a mediocre period of average weather.

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.