Model output discussion - deep cold inbound?

[TSNWK]

10 minutes ago, Battleground Snow said:

I know it's hard not to worry about the milder air creeping in past 168 on runs, but take a look at the difference from yesterday 06z run to today's for the same time period...

The most important thing is the really cold air should get in by 72-96 now, almost the reliable timeframe.

History tells us that low pressure tends to struggle against a cold stagnant air mass and it usually takes a few attempts to break it down.

 

Wow.  Big difference there between 168 yesterday and today's 144 for next Tuesday.  Uppers being broadly 10 colder  todays run. 

And to think in the south we only need a couple of degree shaved off to be safe in the initial sliders.   We can work on that I say.

Edited February 3, 2021 by TSNWK

[jimbo36]

3 hours ago, DCee said:

But the ECM has moved towards the GFS and the GFS has stuck with the initial cold for midlands north. So I'm right in my initial analysis thankyou.

Agree with @Djdazzle, once again talking rubbish.

A proper forecaster suggests that the ECM, UKMO & GEM have been the most consistent models since the weekend for this E'ly solution, UKMO in particular - 00Z UKMO would keep the cold in place well into next week & pick of the bunch for that is the 00Z EC with potential frontal snow too.
Goofus can be taken with a pinch of salt. It's on board for now, but not going to take much notice of it going forward if it goes against the consensus again

[winterof79]

2 minutes ago, MJB said:

Decent enough mean 126h

Yes and when next year's looks like last year's we will realise that it's not just decent it's fantastic

 

[ALL ABOARD]

Control much better for longevity.. 

Heights remain high to our north and force the jet stream south. 

Increasingly cold dense air becomes stubborn to shift and frontal systems slide as they engage it. 

 

[ICE COLD]

Unbelievable morning . I’m so excited . 
 

Across the board stunning . ECM, UKMO,GEM , GFS ,ICON. 
 

Im so excited  

Edited February 3, 2021 by ICE COLD

[ptow]

28 minutes ago, Anthony Burden said:

Morning all latest GFS beginning to show stronger northern blocking keeping the very cold/cold

north easterly going.My take after initial low pressure to the southeast on Sunday bringing some 

snow,a mostly dry Cold/very cold period with Atlantic lows forced further south due to increased 

pressure rise to the north.

 

Am I missing something. the GFS06z has sw winds and postive 850's right up the country by next Thurs?

[Battleground Snow]

GFS op looks a bit keen to let the Atlantic back in compared to the mean at 168. Nice colder cluster there too.

 

[snowspotter]

1 minute ago, ptow said:

 

Am I missing something. the GFS06z has sw winds and postive 850's right up the country by next Thurs?

Yes probably , the trend is for a more prolonged cold spell across all the models . Just this particular run brings in sw winds . 6 hours earlier the GFS run. was more prolonged

[Ali1977]

2 minutes ago, ptow said:

 

Am I missing something. the GFS06z has sw winds and postive 850's right up the country by next Thurs?

No that’s what it’s showing, hopefully beyond Thurs it’s showing as an warm outlier within the suite.

[Tim Bland]

Looking at the precip ensembles it looks like the op is. Dry outlier (if that’s even a term!) for the south east. Most members have more in the way of showers penetrating well inland (these are for St Evenage ..

[Don]

21 minutes ago, kold weather said:

Something to take note of on the 06z GFS ensembles is that they are becoming increasingly progressive with the LP in the Atlantic between 96-120hrs.

It doesn't have to be a problem away from the far south possibly, as I suspect any push on that low is going to be well south of the UK, but its worth just keeping an eye on in case it gains any traction on the models within the next few suites. 

This is nail biting stuff for the far south indeed but at least we are still in the game, just don't take it as a done deal yet!  I think those further north can just about relax now though!

[Buzz]

1 minute ago, ptow said:

 

Am I missing something. the GFS06z has sw winds and postive 850's right up the country by next Thurs?

It's 8 days away, model output is highly variable the further away the output is; it possibly won't happen that way, if at all. Don't pay too much attention to the output more than 5 days ahead in this kind of setup, just take it on board and file it away as a possibility.

[SqueakheartLW]

1 minute ago, Don said:

This is nail biting stuff for the far south indeed but at least we are still in the game, just don't take it as a done deal yet!  I think those further north can just about relax now though!

I know you say this but who can forget January 2019 when the easterly just vanished and we ended up with that warm spell come February 2019 or the ECM easterly in 2012 that mysteriously vanished just before it was due

[SqueakheartLW]

1 minute ago, Don said:

This is nail biting stuff for the far south indeed but at least we are still in the game, just don't take it as a done deal yet!  I think those further north can just about relax now though!

I know you say this but who can forget January 2019 when the easterly just vanished and we ended up with that warm spell come February 2019 or the ECM easterly in 2012 that mysteriously vanished just before it was due

[Don]

Just now, SqueakheartLW said:

I know you say this but who can forget January 2019 when the easterly just vanished and we ended up with that warm spell come February 2019 or the ECM easterly in 2012 that mysteriously vanished just before it was due

Yes, that still haunts me today as I'm sure it does many others!  How close did the cold spell come before disappearing on those occasions?

[Jeremy Shockey]

GEFS 6z ensembles

Looking very cold until 11th at least.

I would not look much beyond that date at the moment to be honest

[mountsbaysnow]

3§q

[Ice Day]

Excellent set of GEFS for my location

Well, I thought they were excellent before looking at the north east of England 

Pretty much as good as it gets for you lot!  

[PiscesStar]

2 minutes ago, Ice Day said:

Excellent set of GEFS for my location

Well, I thought they were excellent before looking at the north east of England 

Pretty much as good as it gets for you lot!  

How do I find this please 

[frosty ground]

19 minutes ago, ptow said:

 

Am I missing something. the GFS06z has sw winds and postive 850's right up the country by next Thurs?

Everything from Sunday until Thursday.

[pages]

54 minutes ago, kold weather said:

The set-up at 168hrs screams of the precipitation ending up staying over the channel and the cold staying embedded over most of the UK bar perhaps the very far south where an onshore flow will raise temperatures.

Following on from that a stronger attack from the SW gives front edge snow for the south and probably much more sustained snow to the Midlands northwards.

I know we don't see Mogreps. But all models we see are very slowly trending to what it must of been showing all along. Met office saying pressure rises directly north and snow showers into east with Atlantic not getting in next week with it becoming dry.

Suggests low on Sunday still be further south than any model currently shows.

[Nick F]

Those worried about marginality in the south where showers come along from the east Sunday onwards, it looks fine on the 06z GFS from Sunday breakfast time onwards away from immediate coasts, with dew points from then on widely falling below 0C and partial thicknesses (850-1000mb) falling below the 129dm needed for snow - which shows the inherent dryness of the continental flow when it gets inland. 

Northern areas no problems with marginality right through - the air will be pretty dry at the surface, so snow will be of the powdery nature I'd imagine.

Only really Wednesday afternoon onwards does the model try and push in milder air from the south. But as others have mentioned, the models can be too progressive in pushing in milder air against dense cold in situ, not helped by the GFS bias of blowing up lows in the Atlantic.

There is a very strong jet powering across the N Atlantic next week, fired up by extreme cold over eastern Canada / NE USA - but, for now, the jet stream is being forced quite far south over the Atlantic towards the Azores then on to Iberia by high latitude block over Baffin and Greenland.

Models now agree on the low pressure over Ireland rest of this week sinking south and merging with low pressure moving NE from Iberia across France and onwards towards the Low Countries this weekend.

How far north the low gets in relation to the UK is still where the models may differ over the coming few days before they settle. It looks now that any warm sector will stay well away over the near continent with this system. This will make the difference to the depth of cold across the south and also amount of dynamic snowfall from fronts associated with the low over the near continent or snow from showers off the North Sea (depending how far north the low gets). For the north, deepest cold here more certain, this will bring the classic heavy snow shower generation over the North Sea - thanks to steep lapse rates of cold air aloft over warmer sea temperatures. Will be some big totals towards coasts from Norfolk northwards - especially the NE.

Edited February 3, 2021 by Nick F

[Ice Day]

5 minutes ago, Snowfish2 said:

How do I find this please 

WWW.METEOCIEL.FR

---

Diagrammes des ensembles GEFS de la NOAA (graphes ENS GFS). 21 scénarios de GEFS.

Then just click on your location on the map

[nick sussex]

The area to keep an eye out for is towards Scandi , after the main block shifts further to the nw the wedge there is crucial to keeping the jet south of the UK.

Ordinarily when you have a more western based negative NAO the jet will try and lift ne towards the UK.

The wedge to the ne is trying to stop that .

You can see the differences in the handling of the wedge across the outputs .

The UKMO has a stronger wedge at day 6 ,that is what you’re aiming to see.

Compared to the GFS 06 hrs run which weakens that . At this point I wouldn’t worry too much about post day 6 as the earlier detail still isn’t sorted out .

[kev238]

The ECM is magnificent for snow across much of UK

Things are looking very promising . I don’t think it will backtrack but another 24hrs of runs will surely solidify confidence