comet

Whoops was meant to do this a couple of days ago, 0.6c here.

There are some cracking ensembles to view. After the bareness of the last 4 winters an almost countrywide snow event bringing 6 to 12 inches of snow would go some way to compensate but if it all implodes and we end up dry and cold with the wishbone effect then that would really rub salt into the still open wounds of the last few years.

excellent run so far only problem being the adjustment south of the low in just 6 hours from the 12z. At this rate by this time tomorrow we will be wondering what all this talk of snowmagedon was all about when the low is modelled 500 miles or more to the south of the UK.

Hoping the 18z does not wind the low up like the 12z it makes it less believable plus of course it introduces less cold uppers and higher dewpoints..

Seems to me they are playing catch up. Signs were there long before now. Lol we could still all be wrong.

I see other posters are now jumping aboard the cold train for December and perhaps onwards although with different reasoning my own and others although if all roads lead to winter nirvana then who gives a jot how we get there. Ecm this evening does seem to fast but can not be completely discounted. Love to see the gfs somewhere near correct (not quite as deep a low) giving a countrywide major snow event. Massive difference with the gfs extended output between the 06z and 12z the 06z throwing a strong Alaskan ridge into the Arctic but completely missing on the 12z thus not as amplified until FI near the end. 0

Why put so much emphasis on what the Met have to say. They have Been spouting cold for the first half of Dec for a week at least, now if it is going to be milder it does not fill you with confidence in what they have to say when they could not see this coming until it's right on their door step. I said yesterday or the day before no one has a crystal ball. Let's see what this afternoon and this evening bring.

My exact thoughts when viewing the models this morning. Keep the faith people's the freeze is just delayed not postponed.

Well that ecm op run was a stinker from as early as 120 onwards as the Atlantic low deepens and heads north, certainly was not expecting that and of course the following synoptics were impacted with zero ridging etc. Really hope and reasonably confident that the ECM is modelling this all wrong judging by the gfs and ukmo runs this afternoon. The pub run should give us a clue with tomorrows runs hopefully confirming one way or other.

I think most posters on here know where our weather is heading from the middle of next week and that is into the freezer. It could be for quite some time as well. should be an excellent afternoon and evenings model watching.

You almost could not draw it any better, and all just 8 - 9 days away. I know at that range it is still a long shot but it is also very plausible.

This is lining up to be a pub run special me thinks.

Very true. Sometimes though the models make problems that are not really there ie inventing annoying little shortwaves etc that mysteriously disappear on later output or get brushed aside by a longwave pattern conducive to northern blocking. More than happy with this afternoon and evening model output overall and fully expect to see a much improved ecm tomorrow.

Her latest update will not be very accurate if the 06z gfs run verifies. Remember we are all amateurs on here there are no experts with a crystal ball. the UK model was the first to delay ridging in the Atlantic because of trough disruption while the other big two went ahead guns blazing now they are playing catch up. We could be on the cusp of something special and while I have lost all faith in Mr Cohen it would fantastic if he was right for once. looking forward to the afternoon and evenings runs with great expectations.

That's true lets just hope it stays there.

The Canadian warming that we saw late October early November is still playing its hand and that is why we have this northern blocking and Atlantic ridging that we are seeing in the models. I would not be overly concerned by the ECM run this evening best to wait and see where we stand in the morning. Have a feeling there will be many relieved posters by then. What does concern me though is what the gfs strat charts are showing in the longer term with warming at the 1mb level not penetrating into the Vortex but rather skirting around the periphery as if stirring and strengthening the vortex.

Yes it is going to be rather cold to cold with some lucky locations seeing snow but it is a long way from a big freeze. Even on the coldest days to come IE Wednesday to Friday any lowland snowfall over England will not hang around for long with max temps of 3 or 4c, Having said that the charts and the weather are 100 times more interesting than what we have seen the last few years and of course there is a real possibility of a potent cold spell (perhaps freeze ) in the not to distant future.

generally speaking away from cities and coastal areas a good rule of thumb from late November to late January is add 10c to the upper 850 temps. For example if you have 850's of -6c then the surface temps will be around 4c. It works pretty well for my area which is about 75m above sea level. Inversions are a different matter of course and also once you get into February the lapse rates go up so by mid Feb its around +12 and +13c at end of Feb. Television forecasts always seem to over do temps for some reason or other.

The breakaway portion over northwestern Russia, very interesting with the direction that is heading. If the flow to the north east connects with the low over northwestern Europe then the uppers would soon plummet. All academic at that range, but nice to ponder what could be.

Well if its prolonged cold you want then you could not ask for much better chart than the ecm t240 chart below. The ukmo run this morning is again less than enthusiastic on cold reloading, but both the ecm and gfs see further amplification in the north Atlantic. The ecm being by far the best for cold prospects from the north and east. For most of us though a rather cold week to come with a lucky few seeing some snow.

agreed an East based nine is better for our chances of cold, So they say.

Silly what ifs aside the ECM looks pleasing to the eye but synoptically far from winter nirvana. I mean if the run is fantastic etc etc now, then where do we go if say in a few days time it was showing -12c 850's across the country for example.

More seasonal type weather on the way by the looks of things but a long way short still of anything resembling a potent cold spell just yet. Far better though than mild rainy mush. It would not take a lot, a tweak here and there to see more noteworthy colder uppers thrown into the mix though.

Would not be surprised that the heights and blocking being shown on the h500 charts are the results of the wave breaking towards the end of October over north America and Canada and subsequent weakening and split that followed in early November as seen below. Just trying to make sense of where these heights and blocking being shown in the synoptic charts originated from. if this is indeed the case and I am pretty sure it is then it does not look as though their has been much if any disconnect between mid strat and trop after all. In fact it is just a lag effect as vortex weakening and split worked its way down and slowly starts to manifest itself in the trop charts.

Couldn't agree more.