Model Output Discussion - Spring Has Sprung

[ANYWEATHER]

Looks like the Easterly winds may be a theme as we move into March ,whether it's going to be a very cold affair remains to be seen ,but at least things will start to dry out ,

[stodge]

What GEM 12Z OP does is develop the core of heights not over Scandinavia but north of Norway (up around Svalbard) which allows a pulse of cold air to extend south west from a small LP over western Russia and that flow of cold air eventually makes it to the British Isles.

The vast majority of other output keeps the heights over Scandinavia so any colder air is steered toward south eastern Europe.

[Mike Poole]

ECM clusters tonight, from T192 right through:

It is cluster 2 (on both timeframes) that continues to provide interest for me, as this one could potentially draw some very cold air from the east/north east.  The Atlantic low looks to stay camped west, allowing for the UK feed to be from a continental source.  Cluster 1 also has blocking highs to the north, but never oriented such as to bring air from the east, and the UK is in mild air.  Could easily go one way or the other here.  

The zonal wind reversal looks to be really quite severe now:

The mean is bottoming out at about -18m/s.  Expect the models to firm up on things a bit once the reversal happens about next Monday, the main effect of that to be seen in the trop may still be beyond the 2 week range, but something is suggesting quite a quick response in what we are seeing already - interesting times.

[Daniel*]

Cooler options are creeping in 12z yesterday and today. 

 

[Rain All Night]

9 hours ago, Rain All Night said:

0z/6z ensemble means, Wed 28th to Thu 14th (day 15)

The main question for now remains, will we see some dry days from 6th March, or will the Atlantic trough stay too close?

0z deterministic runs, Wed 6th (day 7)

12z ensemble means, out to Thu 14th (day 15)

These means make me feel as though a modest dry/continental spell some time from the 6th March onwards is perhaps a little more likely than not at the moment, though some miserable outcomes still remain on the table. I don't feel we've learned a huge amount from this afternoon's runs.

12z deterministic runs, on Wed 6th (day 7)

I'll take ECM or ICON home tonight - Scandi highs are pretty.

  

Edited February 28 by Rain All Night

[WYorksWeather]

GFS 18z is in an interesting rollercoaster ride. A cold spell until around day 6. We then drag in almost a plume-like setup, probably very mild at the surface for a time. Around day 11 or 12 the flow then turns easterly, and then right at the end we look to setup another southerly flow.

Charts at days 5, 10, 12  and 15:

Would be interesting if this were to verify - bit of something for everyone at this time of year maybe.

Don't have time to wait up for the complete ensemble unfortunately. Been quite busy lately - hoping to have time for a bigger update in the next couple of days.

[Lukesluckybunch]

Nice looking icon this morning..easterly becoming established by day 6...gfs and gem not keen on the easterly..with perhaps more of a milder South/southeasterly..last night's ecm mean looking pretty accurate!

Edited February 29 by Lukesluckybunch
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[Ali1977]

GEFS Mean Friday and Saturday  - snow chances keep increasing, im quite hopeful of a decent covering at some point!! ️ if places fall the right side of marginal there could be some decent depths 

[Lukesluckybunch]

Day 7 ukmo! Very close to that cold pool over the continent..what could go wrong!?haha

[Ali1977]

 Lukesluckybunch all good stuff, best part of winter in March is becoming a pattern of late. Earlier we get this in March the better obviously , we can still get ice days if it falls right. 

[Lukesluckybunch]

Day 9 mean..not bad and improvement on the 18z..more of a undercutting look

[TillyS]

The signal for the Scandinavian High next week is strong in the models now. Nothing majorly cold but it would bring settled conditions there and, by extension, to the UK for a while although not particularly cold.

On a personal level I’m happy as I’m off to Norway today for a fortnight. Loads of magical snow on the ground in the mountains, nice conditions for adventuring, and a slightly increased chance of seeing the northern lights when I get into the arctic circle  Pot luck though.

GFS and UKMO for middle of the week:

 

Edited February 29 by TillyS

[Lukesluckybunch]

4 minutes ago, TillyS said:

The signal for the Scandinavian High next week is strong in the models now. Nothing majorly cold but it would bring settled conditions there and, by extension, to the UK for a while although not particularly cold.

Yes it's now looking likely..I have to agree with you,not looking overly cold at this moment...we are approaching the time of the year,where the set up has to be perfect!as the sun is gaining strength now etc...

[Lukesluckybunch]

Currently this morning as we stand..it's ukmo and icon..vs gfs gem!let's hope the ecm brings us a clean easterly

[RJBingham]

More of the same, nothing particularly cold, or warm

 

[Lukesluckybunch]

Ecm day 7!lovely strong hp over scandi!

[feb1991blizzard]

Best ens member -

[IDO]

It looks like we still remain west-based, so any Scandi high will have minimal impact on dragging any extreme cold to our shores. The GEFS mean from D8-16 highlights this:

 

There was no sub-tropical forcing to help, and the mean tPV returned to the Arctic region in that timeframe. The 850s cold bottled up over the Arctic with no split tPV. 

The London ens (850s) looking average from next week:

EC also keeping the cold away from our shores due to the trough to our west, next week (to D10 850s):

As for the nearer time frame, a colder 2-3 days, though nothing unusual, may bring snow to some, but hills and mountains most likely:

And, of course, M4 North!

We remain on the cold side of the jet, so any forcing could bring cold in quicker than we usually have to wait, but at the moment, we are outside the periphery of where we need to be for a snowy end to the winter.

[TillyS]

On a selfish level this is looking extremely good for me. I’d like to have seen falling snow but I’d definitely trade that for the northern lights, especially as there will be loads of snow in the mountains:

It’s still not an especially cold set up for the UK. A nippy south-easterly but empirically not (at the moment) showing very low temps.

Right, time to head off to Norway. It was partly the scarce snow up in Scotland that decided me on this.  

Edited February 29 by TillyS

[Neil Harris]

 Lukesluckybunch Are we looking at a spell of dry weather with this, Cheltenham needs to dry out?

[Penrith Snow]

The snow level on Friday is being lowered as the time approaches, anywhere above 400 feet in Northern England is in with a chance now.  The Lake District being the sweat spot.

Further out a cold easterly is looking more likely but at the moment cold rain and sleet more likely than snow. This however could be upgraded.

Little sign of spring.

Andy

[Lukesluckybunch]

25 minutes ago, Neil Harris said:

Are we looking at a spell of dry weather with this, Cheltenham needs to dry out?

I would say drying out midweek onwards..looks still a bit wet early in week

[Cheshire Freeze]

GFS is very wet for SW areas. Edging 100mm more rain in the next two weeks

[MJB]

4 hours ago, Lukesluckybunch said:

Day 7 ukmo! Very close to that cold pool over the continent..what could go wrong!?haha

D10 on ECM not far off something good 

Edited February 29 by MJB

[Lukesluckybunch]

3 minutes ago, MJB said:

D10 on ECM not far off something good 

True..just have too watch that low to the southwest..doesn't spin up and destroy the pattern..but the hp looks quite strong..and in a decent place!looking at that chart ,looks like we could have a blast from the east..or a slower route to the cold from the northeast!I think we have two chances there

Edited February 29 by Lukesluckybunch
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