feb1991blizzard

Not bad - especially considering trop is nothing outrageous either.

Met4Cast That's what i always thought, but there has been times before where it has died into COD and re-emerged in a phase not far away from where it died.

Met4Cast True but if its a decent SSW then it could write off the SPV, surely AAM will rebound at some point during the next 30-40 days giving us another shot at some point.

Look what's here again,

Scott Ingham Cant remember exactly, early - mid feb i think wave one and then wave 2.

Scott Ingham Yes, that's the best Strat chart i've seen for a good 5 or 6 years.

johncam The vortex is split (favourably) right the way through the atmosphere. If you look at the charts you will see the low numbers (heights) either side of a ridge (high numbers), that means there is two lobes of vortex split far and wide.

BOOM!

Lukesluckybunch Coming down from the North in a minute. frosty ground It can be a stonker as in a stonker for cold and snow - model run, doesn't mean it will verify.

GFS is going to be a stonker.

These are the charts we need to be seeing more of.

That last post its posted the wrong charts.

Interesting Stratosphere charts, a wide split @ 20mb, not so wide as you go down the layers but then not a defined Canadian segment at all higher up Which looks like a trop induced wave 2, but the 0z GFS was as flat as a pancake.

bluearmy WOW, looked a downgrade on recent runs on the graph, it must be that the pattern is there and had the graph gone on another week, there would have been a hefty cluster of -10c flatliners.

bluearmy If this is as far as it goes and then it just reforms then we're in trouble, but if splits far and wide eventually with a 1000 mile + ridge separating the daughter vortices with one in Siberia and the other in Canada, while it may delay the cold a short while but could mean a real sting in winter's tail and i know not what you want but a write off for the first half of spring in terms of outdoor activities (barring skiing) and with a Euro's year throw the football season into chaos.

bluearmy Oh they're back - thanks. Interesting chart right up top.

bluearmy I am usually massively in favour of splits but on this occasion, i can't see how after the displacement we get the w2 through Greenland to Pacific and safely get cold in as the vortex needs to get back over the pole first (fraught with danger) , the problem is (as you can see in T216 charts) is, we need a N'ly first to get roper cold into Europe, then we need a mechanism for it to head west, i'm struggling to figure out the synoptics at the moment (doesn't help not having GFS strat height charts for a while now mind)

if this went out further.........

bluearmy Yes, if we get a split, it needs to be a) wide, b) favourable placement of daughter vortices and c) coupled with trop for decent amount of time, too much can go wrong, problem is it may be the only way to get a -13c - 15c Easterly, albeit in March!

Lukesluckybunch GEFS are an improvement but come with a big red warning for accuracy, have you ever seen a 12c 850mb temp spread at Day 2.5 before?

Icon 0z is hideous.

19th-26th should settle a few nerves in here again.

Cheshire Freeze Yes - SSW likely now.

Daniel* Normally i would agree but the ens are trending the wrong way too.

nick sussex No - if anything its worse, snow / rain boundary further North.