ZK099

Spectacular mean showing heights in Svalbard/Greenland area. As many of the more knowledgeable on here have said, when the ENS signal is that strong, it's usually on the ball, or thereabouts. Likelihood is that we will see extensive northern blocking. The only issue is whether it will be positioned and orientated favourably to deliver cold to this isolated, lonely island...

This doesn't make any sense. How on earth is the PV still present in Greenland after such a massive strat warming and reversal? It's that which is preventing heights building north towards Greenland. Something isn't right here.

Good post, people really should take a look at the link. Explains why models may be struggling here.

The SSW still hasn't fully occurred and the models are still trying to get a grasp on it. They've gone back and forth for a few days now. I really don't like the look of this morning's runs but we should stay patient. Whatever the models are showing by Wednesday, we can be fairly confident that that's what will happen I think.

Hard to beat pneumonia and sepsis as I've witnessed from personal experience. Respect.

What about 1987? Edit- didn't notice someone already picked it out!

People are calling the cold spell (which hasn't even started yet) dead already hahaha. This forum really doesn't fail to amaze me at times. The SSW HASN'T HAPPENED YET. Wait until it happens, and then talk about extended EPS. The way some of you talk about model runs you'd think they're right every time. In the last few runs, in terms of GFS, we've had Greenland highs, Scandinavian highs and Arctic highs. That's the sort of theme we need to continue.

Polar vortex in Greenland causing issues here. SSW might sort it out imminently though...

Now I'm not an expert by any means, but I think people are paying far too much attention to the models. There are numerous changes in the atmosphere currently underway and the model output in a week's time will be vastly different to the output we're getting today, that's for sure. It's more important to look at the teleconnections at this stage. There are three main big factors for me. 1) Massive MJO pulse in a blocking-favourable phase. 2) A very clean SSW with a split. One look at Judah Cohen's tweets and it's evident that this really is significant. Likens it to 1985, which was one of the coldest in history for the US and was bloody cold here too. 3) Low sunspot activity- correlates with colder winters here in the UK. The teleconnections are aligning so to speak. Have patience and in 7 days the models will hopefully have clocked on. Until then, expect some bizarre output!

March warmings come too late to have any wintry effect

Not sure how good this would be for North East England. These sort of synoptics are perfect for South East and Southern England really

For what it's worth, last week's cold spell wasn't really modelled to deliver much snow and up until the last minute, uppers looked mediocre. However, in Newcastle in my area at 130m, I had the most snow showers I've seen in years thanks to a late trough in the North Sea. Moral being, even if certain areas aren't modelled to be hit with snow, surprises always pop up, especially in such an unstable flow. So I'd say the vast majority of the UK has a good chance of wintry precipitation from Thursday onwards.

Reckon there's a chance of a polar low forming...?

Anyone reckon there's a chance of a polar low developing in that northerly flow?

I've gotta say the GFS ensembles are the best I've seen all season for sure. Lots of intra-model agreement as well as inter-model agreement. First time this season there's a very definite drop in temps with less scatter in the GEFS, with some bringing 850 temps below -10 for my area in the North East. Interesting week ahead.

It's in FL so I'm really not concerned with long range output when the models have been struggling with short range modelling recently. The CFS has changed its tune regarding its long range forecast already I think so it's still all up in the air. I'd rather enjoy this current wintry spell than worry about Christmas for now

This is a wait-and-see scenario. It's essentially GFS/ECM + other lowkey models Vs. UKMO. The UKMO could of course be correct and has been before. But currently the odds are in favour of very cold weather. 00z runs will be the most important for some time as to whether the GFS or ECM remain stubborn or move towards the UKMO. I wouldn't worry too much about the Fax charts atm but the 00z runs will shed a lot more light. Nervous few hours but good model watching regardless

Agreed, but in winter in particular it performs quite poorly compared to Euros. Not sure about other seasons but in my experience the GFS regularly gets it wrong in winter.

This platform is hilarious. Just days ago the GFS was completely off just a couple of days out while the ECM/UKMO were more on the money. This time the ECM/UKMO are showing the cold and people are fully backing the GFS for some reason. One things for sure, I'd rather have the ECM/UKMO showing cold and the GFS showing mild than the other way round. Plenty to be optimistic about imo. GFS has been an embarrassment to its programmers the last couple of winters. Hopefully a similar situation here!

I'm pretty sure they don't haha. Gfs performance has been so poor over the past few winters and it was only last week it got it wrong only a couple of days out

Definitely the former after last week's shambles!

Fantastic blocking. Best since last night. Where are the 'ECM is king' guys now?? ?

Best block since the 18z last night. Maybe, just maybe... ?

If I remember correctly something similar happened in either 2009 or 2010. Models repeatedly showing HLB and cold for UK, then signal dissappeared and then reappeared a week beforehand and verified. Still all up for grabs but hope something similar happens here.