Leaderboard

Stopped looking at ECM tonight at 168. It’s one of those times, that no matter what is modelled before day 10, I knew that T+240 would show a Greenland block scenario. And sure enough I just looked and the Atlantic amplification is there towards Greenland. Back in 2010, we knew the destination, but not the route there. I’m beginning to get that same nostalgic feeling again.......

GEFS GET IN - BOOM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Eve - Not often I give favourite here but UKMO solution ( similar to its all conquering 2013 run ) its as high in my eyes as 75% JMA 144 very similar & extends to 192 = 2013 nirvana ( who remembers March 2013 !!)

Good evening all Around a week ago I posited that we were in for a short mild spell which would be but a prelude to the next exciting phase of what really has been a fascinating winter of NWP analysis. The following GFS 384 chart was used for illustrative purposes as to how we might get there... The recurring pattern of the winter, heights scrambling towards Greendland and a trough angling down through the U.K. into Europe. This solution still very much in evidence on the models, the day 9 ECM for example This could lead to a cut off Greenland high. With the jet undercutting and a high risk, high reward scenario following, GFSP goes along these lines Pleasingly, the flatter mid term solutions such as the ECM op from 2 days ago are less prevelant. It’s hard to separate happenings in the stratosphere from this shift in trop output. Would we be seeing GHs and charts filled with anomalous wedges with a raging coupled vortex? Of course not. Are we seeing them due to a downwelling wave? I’m not sure... Inconclusive, but that’s one for the experts to dissect. We’re Interested in the very bottom right of that chart, and the trend at present is that of a lightening of blues. But there is a 3rd solution. That is, the wedge of heights from the N around Tuesday that has been predictably poorly modelled could establish to the NE and send the Atlantic energy underneath as early as a weeks time. The UKMO and JMA manifest this evolution, but it’ll need to be there in lights across the board come tomorrow evening to have any chances of verifying. But 2013 tells us it’s possible, so one to keep an eye on. A quick look upstairs tells us this is no ordinary winter A mean reversal for the duration. Potentially 20 days easterly and possibly beyond, with a really strong signal for another full on SSW in the extended. The net effect of this extended reversal will be felt across the hemisphere for many months. And what then of the mighty seasonal models, the motley crew of humbugs who wrote of winter before it had begun? Well it doesn’t look good, the votes are still being counted, but the early polling is heralding a landslide defeat. ECM FMA from Dec run Latest run A caveat here that some members of the Dec EC run did see the SSW, hence perhaps the no signal over Greenland and slight encroachment of lower heights near S England. Always a model to into account, whatever the lead time. Meteo-France JFM from Dec run Latest Oops Now, DWD, only temps and precip anomalies are available on their site, but a glance at the latter tells you all you need to know... Dec run for FMA Dry anomalies over iberia, not great. Latest run Dry to the N, wet to the S. Jet equatorward and cold/snowy possibilities you would imagine. Even the grinch fancies a bit of the January blocking action, reverting to type in Feb Cansips has similarly flipped. I will reserve the final sentence for the December seasonals until the vanguard GLOSEA run shows its final hand, but it looks like curtains to a strongly westerly winter to me. Looking forward to this place getting busier in the coming days and weeks!

UKMO 144 now edging towards the 2013 scenario as more & more energy slides SE ( would be 156 /168 ) on the face of it @snowking @Paul Sherman

Lol. Perhaps I better not post for a few days. But I haven’t seen such a strong signal for proper cold in a long while. We have strat, a small amount of tropical feedback reinforcing an excellent underlying early winter pattern. The solar cycle of early ascending phase seems to reinforce these blocking patterns too. Why? I’m unsure of. But all in all, let’s stay calm and see how this unfolds, because we have already experienced fantastic synoptic output this winter for very little surface gain. Unless you have altitude and distance away from coastal modification on your side. But that may change in the last third of January.

Ladies and gentlemen we now have the big stand off...the big event..to the West we have the rather lame and uninspiring Atlantic..To the East we have the Beast...with more power than strongman Eddie Hall...some ridiculous cold uppers being highlighted now..This could get tasty And I feel next weeks milder weather is becoming more of a blip before the main course.

137 layers-wow, I am old enough to remember the frist Met O computer, belonging to Ferranti Manchester. It had THREE levels. Can't find the article on it from 50 years ago but I'll keep trying!

Lol this run could be heading towards a Friday evening pub run special brew. Let’s keep watching.

Well, another cracker. Daytime max of -5.2C, 8.30am minimum of -6.2C. Ice day and road temperatures must be mental - on B Road to BIggar, covered in snow, car saying -15C. 4 cm extra last night. Squeak squeak: (There's a lake there somewhere!)

Afternoon all. Just have received a snow forecast up date and the latest model indication has put us over here in high class category alert for substantial snowfall in resort for Wed/ Thurs next week with 50cm or more fresh snowfall. You might also be interested that in the parameters, risk of snowfall has been flagged for the spine of the UK ( same time ) I would view that as the Pennines. Have not seen the models this morning but would assume possible transition or boundary snowfall at height. Will have a more in depth update tomorrow from our portal service with view to you guys going forward. Now I ask is the present UK cold spell on the wane or not.? C

What a beautiful day

Finally some eye candy for the South..

Fantastic run...basically become an extension of the Arctic.

GFS catching up here..... Another dusting here

Glorious winters day. Nice to see the snow hanging on the trees as opposed to melting not long after falling. Walked down to Shawlands for a cold doorstep visit with my sister. Great photos from everyone today. Hope there a few more days like this before spring kicks in!

Beautiful morning out there with temp well below freezing.

Yessssss....

Can I say, I know we've been lauding the GFS for certain "wins" recently *but* in this instance, I think we've seen in the past the UKMO will beat it when it comes to wedge/slider scenarios - in which case, it isn't really worth taking today's GFS in FI too seriously because it will already be so wildly wrong by D5.

Well, this is how it usually goes as SSW-driven HLB starts to be picked up on more: ECM and GEM leading GFS considerably. However - we now have the parallel GFS showing that it might actually be an upgrade on the operational when it comes to stratosphere-driven changes. In typical fashion, the outcomes vary in timing and orientation of the major features. The 06z GFS(P) is a nice take, although the cold air has a long sea track hence it lacks a bit of punch compared to what we can see from north of east. Even GFS isn't locking down high pressure over Iberia as much in the extended range, which suggests that there's been a shift toward getting the MJO moving away from the Indian Ocean.

Can you post some examples of when you have got excited over cold weather...just so we know what to look out for ??

The models seem determined to find every possible way of keeping the deep cold to the east from breaking through the UKs defences! The UKMO at day 6 is tantalizingly close to an excellent chart , with a bit more sharpness to that low to the west that could disrupt se supporting the high to the north . At the moment the models seem to be at the roulette wheel on a continued winning streak of avoiding getting that deeper cold into the UK . How long can this luck last for?

Exactly this. With the chaos aloft at the moment, it's only really worth looking at the overall trends beyond a few days. The main things we're seeing: - An Arctic high which increasingly wants to come and play towards our side of the hemisphere - The jet stream running out of steam across the Atlantic - The temporarily Asian based vortex segment wanting to retrogress around the southern side of the Arctic high The detail will continue to vary hugely in between all of that (including whether the UKMO solution has any legs to it in the shorter term), but looking ahead to the latter part of January, all those ingredients keep us well and truly in the game.

That photo of the Ferranti Mercury computer, known as ‘Meteor’, takes me back a bit John as I was at Dunstable in the Napier Shaw buildiung for a short while in 1959

UKMO is way ahead the best run today lows cutting ESE & pressure build to the west...

GFS (p) Backed up so far west we already have snow on the scene Tues!!

So I've had a terrible day. My brother is in hospital with covid. Anyway I've missed all the model output since early today. Are the models and synoptics looking OK today. Sheffield missed the snow today but are things looking good

ECM 96 hrs.

EC clusters look fabulous.. Little wonder Exeter are leaning cold.. I'm expecting this place to get lively, soon..!

What a stunning day! Best winter's day for quite some time! Had a great sledging session this morning. Loads of parents and kids out having fun! Couple of snaps on the way to the hill.

Yipee, found the Met O link, well worth reading, hopefully it can be put somewhere anyone can access it, perhaps in the learning area. History of numerical weather prediction WWW.METOFFICE.GOV.UK The history of numerical weather prediction (NWP) at the Met Office, from the early 1950s to present.

Has snow picture fatigue set in yet ? Well here's some of today's offering from the outskirts of Alford. Still - 2.0C here at midday and with a bit of a breeze at times it feels bitter.

Yes I'm feeling momentum is gradually moving in coldies direction this morning... I would say we are seeing evidence of a pretty quick response to the SSW...

Excellent GFS Run the progression through 240-258 and those N Atlantic heights just remain in situ whilst the weather moves around them- suggests to me it's stratospheric led. I.e not a standard toppler

The 'Classic GFS backdown moving to UKMO' 12z first V 18z

Really sorry to hear that news, wishing your brother all the best and a speedy recovery from the virus.

One advantage to working at home is being able to get out around the village at lunchtime. Stunning day. Car was reading -8 at 6pm.

@Howie @Djdazzle and @Vikos Are your one line responses adding to the thread, or are they just fishing? Adding some solid analysis and charts really help the thread move along more smoothly. If that snowfall in Madrid helps paint the picture for the U.K., elaborate! if the Iberian heights need to move south, then show us. If the UKMO 144 is ‘notoriously unreliable’ then add some evidence. Ive nothing against posting BBQ weather in January (sounds nice!) but be mindful of what your actually posting.

Happy where this is heading, GEM and ECM to add support? (moaners will go on my ignore list, makes reading this thread more healthy).

It's quite rare in the UK to see both a bitterly cold & unsettled pattern at the same time as per GFS 18z, but that would literally bury some areas of the UK in snow, no marginal air there whatsoever and a heck of a lot of moisture. Incredible run. Likely to be completely different tomorrow but we're starting to see momentum building for cold Jan 18th and beyond.

So firstly, low behold, we have that stronger Greenland block on show. All routes lead to.... But why am I so confident so early on that this will be the case? Well it is the difference between thes two charts, one from the 12ZGFS run and the next from the 18ZGFS run. If we we know the destination, then we can pick the better route early on. The above chart is the 18z the below chart the 12z. Not much difference at the same timeframe. But the big difference here at an early timeframe is seen towards the southwest of Greenland. The way the low pressure splits from the main lobe and the difference in heights involved is all important here. Once we see that, we know that reinforcement of any Greenland block is likely to be stronger and quicker in the median term. So so at this point, despite what happens in FI, we know that we are likely to see an Atlantic blockout and possibly some great northern Atlantic blocking

*cough* ....

Never forget 2013... UKMO was all over it & GFS ploughed the energy east!

As you say Griff amazing consistently with last run considering it’s 280hrs !

Kids are going to go mental in the morning when they see this The cat is not impressed though I better get some sleep, looks like it’s another day of sledging Winter 20/21 turning out to be not bad at all

Cracking pics in this thread today! A sprinkling to wake up to, already a couple below freezing. Shame it’s to end but been a good spell of cold weather. 2 week duration, fantastic sunny days, minimal thaw (helped by the weak sun) and snow has fallen in almost all corners of the country (pretty rare). Haven’t read the MOD yet but seems like we’re in the race for deeper cold... Got the Merrick (843m asl) ticked off today as per below: BITTER cold at the top due to a keen wind. Windchill must have been -15c, was painful Lovely views of Ailsa Craig (3rd from bottom), Isle of man, Southern uplands, the hills of Arran etc. Not sure how far North could be seen, certainly up other hills I’m certain i’ve seen the Ochils. In summer on the Donalds beside the Grey Mare’s tail I saw Arthur’s seat etc. The prints in the snow in the 3rd pic (from top) are that of Deer - they roam quite freely in the Galloway forest. FullSizeRender.mov

Perfect morning

Here’s another photo from the south side. Might be a few of these today...

Great wee day until the tailbone decided time was up for me - wrong choice of footwear didn't help, canny blame the snow but will sure blame my footwear! Also, this is on twitter showing temperatures earlier!! STV news at 6.30 had Glasgow down for low of -5 and Lanark at -9 - surely not low enough by Met Office?

A fine cold winters day with a maximum temperature of 0c. A few photos from around the Firth this afternoon with one of the Cawdor Hills together with the hills to the west and north and one of the fine sunset