Jetstream - big cut-off loop in the next few days off Portugal (feeding a Medicane? - see that thread) while main stream runs across Iceland. Situation persists with cut-off getting weaker until about Wed 23rd when a new loop appears and swings across the UK in a rather fragmented way but the northerly course of the stream is restored by Sun 27th which however spins off a couple of cut-offs by Wed 30th , one in the Med and one mid-Atlantic

GFS - LP off Portugal absorbing ex-hurricane Paulette and staying there while HP runs in an arc from mid-Atlantic to Scotland to C Europe, until Wed 23rd when something more W-ly appears for the UK. By Sat 26th appearance of another ex-hurricane on Atlantic helps to push up a new HP over the UK which persists even after the ex-hurricane gets absorbs in the Alantic circulation ; finally the chart for Thu 1st looks remarkably like a repeat of today's.

GEFS - Temp stays above average to Wed 23rd (well above in S) when sudden drop to a little below average and continuing there (with some uncertainty) to Thu 1st, hints of warming up at the end. A little rain around from Wed 23rd with best chances about Sun 27th in the S but earlier in the N. 

ECM -like GFS to Wed 23rd, then much deeper trough across the UK rather than W-ly and LP centred NE England Thu 24th (would fit the temp profile in GEFS better than the GFS does).  The new ex-hurricane noted above does not appear.

Not so different from this morning's ECM

Overall picture from 16-dayer is for a typical NW/SE gradient, cool and damp in the NW and warm and dry in the SE.

GFS - LP around Biscay, a combination of home grown Atlantic depression and decaying ex-hurricane Paulette, now in position with arc of HP around it reaching to N Scotland, lasting until Mon 21st. Generally W-lies follow but with quite a deep trough embedded Thu 24th (995 mb N England) before pressure rising to Tue 29th, when another LP is forecast in Biscay develops pushing up warmth from the S especially noted on Fri 2nd. (doesn't match the 16-day average well) Another ex(?)hurricane 970mb over Newfoundland Thu 24th doesn't appear  to affect UK. 

GEFS - drop-off from warm conditions Wed 23rd, mean of rather variable runs after that a little below seasonal norm, op & control both suggesting a probable warm up by Thu 1st (and in Scotland esp further N also a peak around Sat 26th). Not much rain, best chances around Thu 24th and/to Sat 26th. 

ECM - Similar to GFS though pressure slower to rise after Thu 24th (that bit of forecast still yesterday's 12z at time of posting) UPDATE Not merely slower to rise but today's 0z in fact forecasting a very deep depression (960mb W of Faeroes)and trough extending S-wards to UK by Sat 26th. This depression may contain remnants of the Newfoundland hurricane above which have been absorbed by and have revived an existing LP near Greenland.

Thank god, for the North Sea cooling effect.

Interesting comparisons 2019 2020

Alot lower this year... interestingly was just coming to comment on the Autumn/Winter conditions ocurring to our north on the charts from next week onwards, proper autumn is about 600 miles away currently, and getting closer each week.   The northern atlantic to Iceland looks very active.

Wont be long before the storms rattle into the UK.  IT feels like perhaps this is happening earlier this year, which might be influencing lack of cold build up ad there fore the picture you see

My recollection could be wrong here, but I seem to recall reading a couple of years ago that the summer of 2018 was the warmest on record in England and was the joint-warmest on record with 2003 (or was it 2006?) and 1976 for the UK as a whole.

1989 was in a lot of ways similar in nature to 2018: A very good June and July which were then followed by a less good August. 2006 was a bit like this as well IIRC.

Jetstream well N of Uk to Mon 21st'also fragments in the Med in this time. It then develops a loop to the W of Ireland, running S in the Atlantic and N over the UK by Thu 24th . The loop then progresses E-wards Sun 27th leaving fragments running W-E across southern UK to Sat 3rd.

GFS - LP near the S this weekend surrounded by HP elsewhere, then W-lies developing and ending up with trough covering all Uk Fri 25th (at same time ex-hurricane Teddy is bashing Newfoundland) . It looks as if the energy that Teddy may inject into the Atlantic circulation will give rise to a disturbed period with several LP centres over the week following - Hebrides Mon 28th, Baltic Tue 29th, SW Ireland Thu 1st, mid Atlantic but heading this way at end of run Sat 3rd.

GEFS - From above average down to a similar amount below Wed 23rd and unlike yesterday staying there until slow recovery around Thu 1st; also rather more rain Fri 25th +/- a couple of days ( the S gets a splash this weekend too). A few big rainfall spikes here and there from time to time after that but nothing consistent

ECM - starts out like GFS but Thu 24th dartboard low W Ireland 980 mb moving across UK as defined feature next day, not just a broad trough

I take it the jet stream is heading south then. Predicatable: this gorgeous weather couldn't go on forever for sure.

Ouch!

What sort of daytime maxs are we looking at here.

Mid teens at best lower in the North.

I seem to remember the weather broke about the same time last year and it rained for 6 months, hopefully no repeat this year.

I do hope so because it was around 22C on 19th Sept when I left to go to Dubai for 2 week with 30C min and 40C maxes to meet my fiancee and then came back on 3rd Oct with nasty early cold wet weather for 6 months.  I do hope to see warm up in early October when graph line go nearer as we did not have any warm October days for long time now.

Wetter in week 1 and notably cooler in week 2 in the averaged outlook - even early snow over the Alps 
http://www.wxmaps.org/pix/temp4

GFS - Lp near the S and HP everywhere else collapsing to W-lies Tue 22nd; depression covering UK by Fri 25th with N-ly gales to follow persisting 2 or 3 days; ridge of HP established Thu 1st and more general HP Sun 4th so warming up again later on

(Pressure over the N Atlantic much higher than yesterday in the second week - although ex-hurricane Teddy attacks Canadian Maritime as before ,it appears to interact much less with the N Atlantic than was forecast yesterday, just shows how the models struggle with hurricanes)

GEFS - temps on the slide, down to ca 7C below norm in most runs ca Sun 27th, recovering indecisively to norm ca Fri 2nd. More rain around esp Fri 25th but many runs continue wet despite promises of HP from GFS (Op & control remain mostly dry as shown on mainstream GFS, but perturbations offer damp possibilities). Scottish temps drop off more abruptly but recover a day or two earlier.

ECM looks similar but N'ly gales die out more quickly (but that timeframe is still 12z as I post, await updates)

Interesting to see the “Inverness” snow row is now up to 6 before the end of September:

https://www.theweatheroutlook.com/charts/gefs/gefsens850inverness0.png 

When I upgraded to the 0.5 deg GEFS in the summer I added in additional plots. The Cairngorm grid point should usually show a higher snow row count than Inverness.

https://www.theweatheroutlook.com/twodata/snowrow.aspx?location=Cairngorms#Cairngorms

https://www.theweatheroutlook.com/twoforecasts/ensemble-forecast.aspx?location=Cairngorms

Or from the GEFS chart viewer:

https://www.theweatheroutlook.com/twodata/gefs.aspx?run=na&lg=850&lglocation=cairngorms&charthour=006&chartname=ps_500hpa&chartregion=na-region&p=1&charttag=PS%20500hPa%20(GPDM)

Looking at the Oz ENS for Aberdeen:

With many runs showing uppers going down to -5 @ 850hpa - It really wouldn't surprise me if the tops of the Grampians and Cairngorms saw some early snowfall!?

Big change on the cards really Autumnal weather on the way 

A noticeable drop in temps also , the burner could well go on 

[quote=Gooner;1256576]

Big change on the cards really Autumnal weather on the way 

A noticeable drop in temps also , the burner could well go on 

[/quoteLovely old school chart.....hope we see charts like this in two months time...amplification has been quite strong past few months....]