[Model output discussion 10/02/21]

More of a NNW than a true northerly on the way for the UK itself. More progress inland for the showers on the western side by Tuesday with nice little squiggles in the isobars and a long uninterrupted sea track all the way down from the Arctic, and development of one or two more general disturbances embedded in the showery airstream. Combined with some convection inland, possibly why the ICON 18z still reckons on bringing snow showers in over a good chunk of England as well as Wales for Tuesday afternoon despite 1024mb pressure. 

 

[Model output discussion 10/02/21]

The EURO4 is showing a band of snow for tomorrow morning (from the second of the two cold fronts I guess) across Northern Ireland, Wales, through Yorkshire, Humberside, Lincolnshire and Norfolk. In subsequent frames, though decaying, this moves down to the London area. Looking at the temperatures in front of it, most likely to settle only on the higher ground, but generally below freezing after the front. 

By Tuesday morning, snow showers over Scotland, much of Ireland, with some into Wales and South West England.  This looks like the beginning of that little feature that the GEM is still showing to move down the UK on Tuesday, shown clipping Belfast at 7am. Temperatures below freezing in most places by then.  Happy Easter to all.

[Model output discussion 10/02/21]

GEM 12z keeping with yesterday’s idea of 1-2 centimetres of snow for large parts of England and Wales by Wednesday morning from the little feature running down the west coast of Scotland and down the Irish Sea early Tuesday clipping North Wales and then SE across England, looks like some lines of showers set up as it comes through. Good part of Ireland in the mix too and many parts of Scotland already pasted by then!

[Model output discussion 10/02/21]

Some snow maybe not just for “ the usual places” next Tuesday / Wednesday if the GEM has it right. It’s picking up on the potential for an interesting little disturbance / polar low running down off the west coast of Scotland Tuesday morning, over North Wales by mid afternoon moving down over the Midlands to exit off the Sussex Coast by early hours Wednesday. Maybe gone on the next run, but shows the potential. 

 

[Model output discussion 10/02/21]

GFS op sticking to its guns at 06z with the low developing away from Greenland in a weeks time, wrapping some slightly colder air around it maybe compared with the 0z

GFS 0z 192h.                                            GFS 06z 186h                                                

[Model output discussion 10/02/21]

Marked difference at 192h between the midnight runs of ECM and GFS. ECM goes for a straight northerly blast already into Scotland by that time, while the GFS develops a low between Greenland and Iceland during the previous day and brings it SE to the northwest of Scotland holding the cold air back a while. It’ll be interesting to see what the 06z GFS looks like.

ECM 0z 192h

GFS 0z 192h

[Model output discussion 10/02/21]

That’s more than 100mb difference over less than a thousand miles between central Greenland and the low off Svalbard. That’ll knock him off his board!

 

 

 

[Model output discussion 10/02/21]

The GFS looks like it was more on the money than ECM for the timing of this week's storm and also had the troughing to the north of Ireland bang on from last Friday. The ECM has now fallen in with its american cousin for 0z Thursday. The T+72h fax shows the same trough, results in a real squeeze through Ireland by Wednesday evening and then across the bulk of the UK by 6am Thursday. Going by the GFS, it will be at its worst for most of Ireland, then North Wales, Southern Scotland and Northern England, though windy pretty much everywhere. 

ECM 00z T+72                                            GFS 06z T+66                                       UKMO Fax 00z T+72

 

ECM then bringing some colder air further south for Saturday with a bit of repeat of the transient N-S troughing to Ireland (528 south of Cork, Pembrokeshire to Norfolk), GFS not so keen on the troughing this time or bringing the colder air as far south (528 Donegal to Lancashire and Yorkshire). 

ECM 00z T+120                                       GFS 06z T+114

[Model output discussion 10/02/21]

Lovely bit of convergence between ECM and GFS for the gale midweek, subtle differences in timing now the main difference for the merging of the two low pressure systems between Iceland and Scotland.  ECM still bringing the secondary low in more quickly to Northern Scotland by 0z Thursday, while the GFS keeps with the N-S troughing to the West of Ireland by that point, and brings it through to Scotland by 06z Thursday. Big similarities with ECM for 0z just running it in 6 hours later. 

ECM +120 00z

 

GFS +114 06Z ; GFS +120 06z

Irrespective of the timing, several hours of coastal and inland gales, arriving in Ireland some time Wednesday pm, transferring east across Wales to most of England, easing later on Thursday. Not so severe in Scotland early Thursday due to the slacker pressure gradient of the trough, but picking up right enough there too later on Thursday.

[Model output discussion 10/02/21]

Been watching the system for the middle of next week for a few days now. Modelled to deepen to 960mb by GFS but to lower than 956mb central pressure by ECM, but the main difference is in their handling and timing of the secondary low. The ECM has it whistling through Scotland to the North Sea by 0z Thursday and deepening, maintaining its own centre, while the GFS merges it into a more of a trough hanging down from the main low over the Northern half of Ireland by that time. 

As others have said, the secondary feature might well become the main interest, as it extends the risk of strong winds further south. The ECM solution would take the strongest winds through Ireland across Northern England to the East of England by the end of Wednesday. If the latest GFS has it right, it will bring a period of strong winds further south over Southern Ireland, transferring through Wales to the Midlands during early hours Thursday then out over East Anglia by breakfast time. Either way it's going to be lively!   

ECM +144 00z

GFS +138 06Z

[Model output discussion 10/02/21]

ECM for next Wednesday now more in line with GFS with colder air not extending as far south at that stage. Central pressure of the depression around 948mb on GFS, 952 mb on ECM, both with same track heading over Shetland. Some stormy weather for NW Scotland.

ECM 00z +144

GFS 06z +138

The colder air for the south held back a day on the ECM and not so cold for the southern half of the UK as modelled yesterday, hints of a secondary low developing in the main circulation for next Thursday. 

ECM 00z +168

[Model output discussion 10/02/21]

Brilliant forum and community I have greatly enjoyed following for several years, the winter just gone probably the best so far. We often get some snow in the hills in Wales in March, even last year on the 12th, settled too. 

ECM has been more progressive than the GFS for a few days now in bringing down some polar air for about 7 days time, pressure over the UK forecast to be much lower than GFS too. Something like the ECM could well do the trick again this year, briefly. 

ECM +168 00z

GFS +162 06Z