GFS puts more emphasis on the first of Wed's LPs deepening it to 970mb while the second shows little development until late on Thu. This model matches FAX by Friday. Pressure slowly rises over Britain while remaining low to N & E; on Thu 30th LP moves down from Iceland to affect the whole of Britain. As this moves away E-wards a W-ly regime sets in but could easily be disturbed by the remains of a hurricane dying on the Atlantic but feeding in moisture to the W-lies.

ECM matches Fax more closely than GFS, and then maintains the pressure rise over Britain from Friday at least until Thu 30th.

GEFS in the S temps near norm until Thu 23rd with rain now and 22nd/23rd, after which temps drop sharply to some 5C below norm to Tue 28th. The temps recover and rise to above norm Mon 3rd but with much uncertainty - after a dryish period rain sets in about that date. In the N, the cold spell only lasts 24th - 27th, and there is less warming later; rain not so much at first but a generally wet period from Wed 29th onwards

AIFS; London maxima 15C now, dropping to 10C from Fri 24th, some recovery from Thu 30th, rain at intervals until Tue 28th and again after Sun 2nd. Edinburgh, temps also drop and recover but in the range 13C to 8C, bits and pieces of rai for the time being then something heavier on Sun 2nd.

Yes, the pub run takes it a bit west, but you could still be in the firing line. 

looking ahead, the usual modern winter pattern of any potential northerly snuffed out and ridging collapsing.  the northern arm of the jet just too powerful to allow any blocking

GFS agrees and keeps the N-lies for the weekend. Although there is then a pressure rise, this is located further south than shown yesterday and NW-lies and cold W-lies dominate for w/b Mon 27th. The W-lies are particularly strengthened by LPs near N Scotland moving east; 955mb Thu 30th (stormy there, gales generally for Britain) and 965mb Sun 2nd (almost as bad, but is the remains of a hurricane and while still approaching Britain is as low as 955mb). After that, a quieter but still unsettled W-ly. 

ECM has a greater pressure rise esp in the S which cuts off the N/NW-ly influence. The Hp moves away as the first of the Atlantic LPs above moves in, but less stormy and a day later - 975mb Fri 31st

GEFS -In the S heavy rain Wed/Thu 22/23rd ushering a cold and dry(-ish) spell, down to  6C below norm, recovering by Wed 30th and even rather mild for a while but rain also returning at that date. For Scotland and N England. less rain 22/23rd in the west, and the cold spell a day or two shorter but rain returns earlier, around the 28th.

AIFS - London, maxima drop from 15C now to 10C over the weekend, back up again by Fri 31st, rain Thu 23rd and Mon 3rd but often cloudy with spits of rain in between. Edinburgh, maxima drop from 13C now to 8C to Wed 29th, then sharp rise to 15C Fri 31st, Rain Tue 28th and Thu 30th, again mostly cloudy with small amounts of rain at other times

But will it reach Essex??

😉

Probably, but with the wind it will get blown south and east….

GFS agrees with the early part of this, but by Monday 27th there is a short-lived ridge of HP from the south, and as this traverses Britain winds move from NW into S by Sat 1st when the controlling feature is an ex-hurricane 935mb(sic) off NW Ireland with gales for NW Britain (note- this is not nailed on - some computer models have this hurricane staying in the Caribbean and wreaking havoc there). This feature runs rapidly NE-wards between Iceland and Scotland, dragging a weak trough across Britain Mon 3rd; eventually the pattern settles to a conventional W-ly  by Fri 7th.

ECM agrees with GFS to start with, albeit with more emphasis on the LP over Scotland rather than that over England, but the following pressure rise is weak, and LPs continue to dominate; 975mb off Cape Wrath Wed 29th and 965 mb through NI to the Hebrides Sat 1st, but not the remains of the hurricane.

GEM more like GFS but there seems to be a second ex-hurricane following the first by Sat 1st so perhaps more unsettled after that.

GEFS in the S has heavy rain tonight followed by a drier cold spell to Tue 28th. Mean temps then back to norm but with considerable ens spread (op and control milder but one or two notably cold outliers) and rain for the first week of November. In the N, much less rain for now in the NW but plenty over the Highlands with a snow row figure 14/33 for Inverness however the cold spell is only a couple of days and rain starts again Wed 29th. 

AIFS London maxima down to 10C for this weekend but rising to 17C by next weekend, heavy rain Thursday, a little to follow, next significant amount  Mon 3rd. Edinburgh maxima also dip at the weekend, to 6C, and then rise to 16C over the week, rain at intervals from Mon 27th.

I can't remember the last time we had such an aggressive Atlantic, especially with the Jet tracking a bit more south than usual.

See Pacific heatwave was going to cause a front loaded winter.

Even the met medium and long read average or below average temps for a few days last week.

Thats been removed and normal service has resumed.

Can I get a frost please?

Several colder outliers on GFS for next week ... We might be lucky, it is still early....

GFS Op agrees, placing that new LP 995mb Sutherland Tue 28th; then a slight rise of pressure before the Atlantic takes control again with large LP mid Atlantic through to Sat 1st with S-lies and troughs, mainly affecting  the W, in the stream. Then an ex-hurricane (Melissa?) puts in an appearance from the south and gets to Cornwall as a 975mb local storm on Mon 3rd, running up-Channel and filling. Finally the Atlantic LP re-establishes but moves closer 960mb N Ireland Thu 7th, bringing with in a pool of cold air.

ECM is like GFS but the 'large LP' is positioned close to Ireland and has more effect on Britain as a whole. Ex-Melissa is a much smaller affair and by Sun 2nd is near the NE USA, not looking likely to come to Britain.

GEM has a much more definite rise of pressure after Tue 28th, 1030mb C France with fine weather for the SE but SW-ly gales for Scotland. This model also keeps Melissa on the other side of the 'pond'

GEFS in the S has heavy rain now (not the SW, but returning to the far E) and in the first week of November, with a cold spell until Tue 28th, Ens members after 28th have a very wide spread - the majority incl op and control are mild but there are some ultra-cold outliers. In the N, rain not specially heavy now (but some in the NE), bit fairly persistent through the fortnight after. The cold spell only lasts a couple of days, to Sun 26th, and then  there is less of a spread in ens members, with the really cold outliers absent. Snow row for Inverness has been cut back from 14/33 yesterday to 7/33

AIFS London, maxima around 10C to Mon 27th then improving to 15C, rain now, a bit damp for a few days but nothing significant afterwards. Edinburgh, maxima about 8C to Thurs 30th, sudden burst of very mild weather for two days, then settling to 13C rain on and off to Sat 1st then mostly dry

GFS OP; shows pressure higher in S Britain on Tue 28th, suppressing the second minor LP above, and then produces a major LP in mid Atlantic Thu 30th with a S-ly flow and troughs moving N-wards, that on Tue 4th augmented by ex-Melissa though much more weakly than shown yesterday, 980mb off W Ireland. Pressure than drops in a broad band from the Atlantic to the N Sea, including short-lived centres near S England Wed 5th and near W Ireland Sat 8th.

ECM; the 'major LP' above is much closer ( 970mb SW Ireland) and deepens first into a local storm there 955mb Sat 1st before moving rapidly north and establishing a trough lying close to the W side of Britain from Iceland to Brittany Mon 3rd. Ex-Melissa stays out of this, over the other side of the Atlantic

GEFS; generally, cool to Wed 29th, then just about on the mild side but mean back to norm Mon 3rd. Usual spread of ens members developing by this time. Dry-ish at first except wet in the NE,  rain in most runs from Thu 30th onwards everywhere, heavy in the W.

AIFS; London, maxima rising from from 10C now to 16C Sat 1st before dropping back a little, a bit of rain at first then heavier at intervals from Sat 1st with a couple of cold nights (5C) between the rainy days. Edinburgh, maxima round 10C (cooler at first milder later) from Sun 2nd some wild swings from cool to mild and back, and again. Rainfall pattern as for London

GFS Op 0z produces a couple more shallow LPs for Britain out of the above area of LP, 980mb Irish Sea Fri 31st and 995mb Bristol Channel Sat 1st. Then the action transfers to a track running south of Iceland, a procession of deep LPs there projecting troughs S-wards to Britain Tue 4th, Fri 7th and Mon 10th.

ECM predicts that LP Fri 31st will be deeper, 970mb C Ireland, after that ( yesterday's 12z, I'm going out and can't stay for 0z to download)  a deep depression develops to the west of Ireland and drifts slowly N-wards

GEFS mean temps soon back to norm and staying there but with a lot of ens variation from November 1st; rain holds off  for a couple of days but otherwise regular rainfall for the next fortnight, heaviest around Sat 1st and generally in the west.

AIFS London maxima soon recovering to about 15C, rain from time to time and heaviest Sat 1st and Thu 6th; Edinburgh also a recovery but to around 12C, rain continual though not very heavy.

The outlook looks like one which gives this season a bad reputation for being boring, cloudy and damp

GFS Op 0z agrees with Fax, and then takes the final LP north up the W coast of Scotland Sat 1st. A development on its southern flank deepens 950mb Mon 3rd and follows the same track from SW Ireland up to NW Scotland. Then a further repeat of this pattern, with this final LP managing to push a couple of small secondary LPs across first N then S England Fri 7th. The final chart shows LP filling in with slack low pressure covering Britain Tue 11th.

ECM presents a similar pattern but with the LP from Thu 30th developing deeper and closer Sat 1st 975mb S Ireland before running away N-wards.

GEM is also similar to GFS at first; the LP on Sat 1st becomes a dartboard LP on Mon 3rd 940mb off the Hebrides. However, later on, this model shows a much calmer Atlantic and after Mon 3rd there are gentle SW-lies for Britain with no local LP centres.

Melissa makes a brief appearance on the far side of the Atlantic on Mon 1st but has already filled and is not forecast to affect N Atlantic weather directly.

GEFS shows mean temp soon remaining to norm and even becoming milder around Fri 7th. Dry-ish at first in the S but wetter in the N, rain becoming quite general and frequent from Thu 30th though not particularly heavy in the east.

AIFS London maxima rising from about 10C now to 15C Sat 1st before dropping back to 10C Fri 7th (note disagreement with GFS). Some measurable rain in the week from Thu 30th, traces at other times. Edinburgh maxima mostly around 10C, if anything lower in midweeks and milder at weekends. Rain for the coming week and again around Fri 7th. Both London and Edinburgh have drier periods in the coming fortnight in this model than shown on GEFS.

GFS Op 0z; On Sat 1st this deep LP spawns a secondary 975mb Cornwall which runs N-wards and takes over 955mb Cairngorms by Sun. Once that has moved on, the weather for the following week to Mon 10th is a standard W-ly with LP between Scotland and Iceland, and S England getting the best of any temporary improvements. Then under the control of a mid-Atlantic depression, a shallow trough extends across S England. Melissa appears as a weak feature near the Azores Sun 2nd but its effect is limited to bringing warmth and moisture N-wards - no direct interaction with N Atlantic circulation.

ECM doesn't include the secondary on Sat 1st, and the westerly which then develops is much weaker than shown by GFS with flabby and shallow LPs drifting around and over Britain to Thu 6th. Melissa scarcely noticeable.

GEM mainly like GFS but on Thu 6th a kink in the W-lies brings quite a deep trough across N Britain

GEFS mean temps near norm or (later on) a little above for the next fortnight. Dry-ish periods now and around Wed 5th in the E and SE, but otherwise rain fairly general, sometimes heavy in the W.

AIFS London, maxima around 13C, warmer Sat 1st and cooler Mon 10th, dry at first, rain steadily accumulating from Wed 29th (no break Nov 5th as shown on GEFS). Edinburgh, maxima around 10C, warmer Sat 1st and Tue 4th, one notably cold night Thu 30th (1C), rain on most days, heaviest Fri 31st and Sun 9th

https://www.theweatheroutlook.com/twocommunity/Posts/t24393-Model-output-breakout-thread 

Could the breakout discussion not be a separate thread in the main weather section, instead of shunted to the Forum Arms?

No, it's better in the FA because it's not indexed there.

GFS Op 0z; the W-lies after Sat 1st are augmented by the remains of Melissa which joins in the N Atlantic conveyor having reached Newfoundland on that date. The W-lies persist steadily (occasionally SW-ly) until Sat 8th when pressure begins to rise near S England, and by Mon 10th there is an enormous W-ly wind field between 1040mb Brittany and 950mb NE Iceland. This looks unstable, and indeed by Thu 13th has developed into arctic N-lies over Scandinavia and a ridge of HP over Britain centred 1030mb Scotland. ECM in general agreement.

GEFS; mean temps near norm; a little colder at the start of November, a little milder at the end of the first week. Persistent rain throughout the next fortnight, heaviest in the west esp southwest but a couple of high totals for the far NE around Sat 1st.

AIFS; London, maxima mostly 15C-ish, a bit lower at first and again after Sun 9th, less rain than shown on GEFS and that  mainly Sat 1st, not much sunshine. Edinburgh, maxima mostly around 10C but milder for a few days from Tue 4th, rain form time to time for the next week, then slowly drying up.

GFS - agrees with FAX to Sat 1st but then takes ex-Melissa further north where it is absorbed into a persistent area of LP ca 970mb S of Greenland. This area of LP keeps SW-lies going for Britain to Thu 6th when a trough breaks off and crosses Britain. During this time HP is well to the SE, somewhere between Gibraltar and Austria. On Fri 7th there's a new (dartboard) area of LP 945mb Greenland but HP is further N, ridging over S England, so still SW-lies but perhaps less rain. This lasts for a further week, with the HP becoming stronger until another trough breaks off and crosses Britain , locally 975mb N England Fri 14th

ECM - prefers the GFS treatment of Melissa to that of FAX. The trough on Thu 6th in GFS is a weaker and more diffuse feature in this model.

GEM - also tracks ex-Melissa to Greenland, but then has a closed-circulation LP breaking off from there reaching N Ireland 970mb Thu 6th, crossing Britain with more small local LPs following over (a rather wet?) weekend.

NHC unusually charts Melissa all the way across the Atlantic and has it heading for Scotland Sun 2nd still as an identifiable tropical storm.

Three options for Melissa - take your pick!

GEFS - mean temp and ensembles up and down to Mon 3rd, then very mild for a couple of days before the mean drops back to norm and the ens members start to disagree. In the S/SE, rain now and over the weekend, then dry-ish, some rain likely next weekend too, and more to follow. The SW omits today's rain but has a greater chance of seeing some in a week's time. In N England and Scotland, rain possible at any time, not too much , but often very heavy in the NW.

AIFS - London, maxima mostly around 15C, cooler now, Sun 2nd and from Tue 11th; some rain at any time until Mon 10th when drier (more rain forecast than yesterday). Edinburgh, maxima irregularly between 10 and 15C, rain on most days, heavier in the first week.

https://www.theweatheroutlook.com/twocommunity/Posts/t24427-Winter-2025-26-prospects 

Looks to me like the CPF is running partly from GLOSEA, which has a 0-0.5 ensemble mean anomaly over southern parts of the UK for NDJ, but for the core winter period of DJF it rises to 0.5-1 across the whole of the UK.

https://charts.ecmwf.int/products/seasonal_system5_standard_2mtm?area=EURO&base_time=202510010000&stats=ensm&valid_time=202511010000 

Last year's GLOSEA also had 0.5-1:

https://charts.ecmwf.int/products/seasonal_system5_standard_2mtm?area=EURO&base_time=202410010000&stats=ensm&valid_time=202412020000