https://www.metoffice.gov.uk/weather/maps-and-charts/rainfall-radar-forecast-map 

EDIT 12 hours later, it's been down graded and moved to Friday!

GFS Op - HP tends to persist over the Atlantic SW of Britain and in Scandinavia, Britain in a trough between the two. This trough deepest Sun 8th when 995m N Sea off Yorkshire. Then after a brief rise in pressure Tue 10th, the trough comes back and not until Fri 16th is there HP 1030mb properly covering Britain. It doesn't last - the following week da capo, HP tends to persist over the Atlantic SW of Britain and in Scandinavia, Britain in a trough between the two

ECM - like GFS at first though the deepest part is 1000mb Belgium also Tue 10th. The rise of HP following lasts longer as a deep depression develops near the Azores instead of the GFS which keeps HP there.

GEM - differs from above in keeping HP across Scotland with the remains of the current trough settling along the Channel by Thu 5th. But by Sun 8th this revives to cover Britain between the two blocks of HP. Although this soon moves off SE-wards, a new LP has reached Ireland 1005mb Wed 11th

GEFS - cooling, then warmer again around Sat 7th, back to norm for the rest of the period perhaps a bit cooler around Thu 12th in England, much cooler in Scotland, Rain in most ens members around Sat 7th and again Sat 14th, a few with big totals for England; Scotland gets rain earlier and then stays dry-ish until 14th. 

SE flow normally very dry air and sunnier flow of from the continent?  Will be very sunny and warm from Friday under very rare SE flow. 

Haar then?

https://www.wetterzentrale.de/maps/GFSOPUK00_90_24.png 

Not from the SE flow never bring clouds most from NE flow in Spring to early summer.  Not sure what your problem with it? 

We didn't get a lot of easterlies during the summer but we can still get that east coast haar when they do occur as was the case yesterday here in Edinburgh.

Looking ahead at the latest model output, it is also looking as though we may well get a lot more of that going ahead with high pressure looking likely to set itself up to our north which would then feed in an easterly wind across the UK.

Of course, we're more likely to get haar if those easterlies are originating from the Mediterranean rather than Arctic because that is a warmer air mass overall which would be more likely have more of its moisture condensing out into mist and fog as it crosses those cooler waters in the North Sea.

The latest model output suggests that these easterlies do indeed, look likely to be originating from the Mediterranean and that is why that risk of haar exists.

No, that is totally factually incorrect. A long SEly track over the North Sea will frequently bring haar to many coastal eastern regions in the northern half of the UK. That’s just a well known meteorological phenomenon. In fact, I have just checked and it is indeed mentioned in the Met Office written forecasts.

Yes Richard hate those with passion but se flow have no impact over here to London as come over short sea crossings.  I see 25 sunny on Friday then back slowly to average with possible early sunny cold northerly blast. Tom more fresher with sharp drop in temps with lot of sunshine after this lately miserable dull faux warm weather.

Yes, the south doesn’t suffer from a SEly flow in the same way with much more of a continental influence. It should be warmer and more humid in the south but perhaps a bit unsettled at times. NW Scotland might be very pleasant too.

Haar is rare down here (speaking as someone who lives close to the coast, and is exposed to the north, NE and east).

The only time you tend to get it here is in late spring/early summer, when the first really humid airmasses appear - IF the air gets pulled in from the east, or NE, AND the sea is cold enough, you get mist/fog/low cloud/murk. Later in the season you just get what we've had recently, a slight mistiness / haziness.

GFS Op - the current situation in which Britain lies in a trough between large areas of HP to W & E resolves into a situation with LP in the Channel and a ridge of HP lying W-E across Scotland. The LP in the Channel localise and deepens briefly 1000mb Isle of Wight Sun 8th (I don't see the blowtorch SE-lies hoped for above - these SE-lies have a long track over the N Sea so haar for the E coast but a very good few hot and sunny days for W Scotland). Over the following week HP noses in from the W and SW becoming widely established by Fri 13th before collapsing and allowing LP from the Atlantic to approach NW Scotland 985mb Wed 18th with strong W/SW-lies for all.

ECM - somewhat like GFS but the LP does not localise in the Channel but is more widely over S England Sun 8th before moving to Germany and bringing in E/NE-lies to Fri 13th while the HP makes a much more tentative approach to N Scotland.

GEM - like ECM but adds in LP in Norwegian Sea from Wed 11th which turns winds into N/NE

GEFS - in the S, quite a lot of rain Thu 5th - Tue 10th but also warmer, then less wet but nearer normal temps, another spell of wet and a little warmer around Mon 16th. Temp variation less marked in W but greater in Scotland. Rain much less in  the N esp NE, and mostly later on

I don't think that Richard would hardly ever be happy with the weather in his neck of the woods regardless of what that was like.

Speaking of Richard though, I have noticed that it's been quite a long time since he last posted anything on this forum so I hope he's OK, especially given some of the language that he has used in a large number of his posts with words such as "suicide inducing," and so on.

I know that there was certain times recently when he was logged on but not actually posting anything as his name was often appearing on the list of logged in users who were currently viewing a particular thread, but it has now been quite a while since even that was the case.

A SE flow is good for here as it mostly travels over hot land (i.e East Anglia/Lincolnshire). A straight easterly is usually pretty poor though. 

I can’t imagine any kind of easterly being particularly good for Aberdeen as it will always have to travel over the sea.

GFS Op - current trough covering the N Sea shifting S-wards and becoming focused in the Channel 1005mb Mon 9th; ridge of HP connecting Atlantic and Baltic HPs but not as well developed as previously shown. By Thu 12th the Channel LP has broadened out and moved to Sweden followed by several days of  cold N-lies for Britain and going on to affect the continent. After a muddled few days with pressure generally low over NW Europe, HP pushes in from the SW Wed 18th for England with shallow LPs running over/past Scotland.

ECM - the ridge of HP is much stronger, appears earlier (Fri 6th) but declines more quickly than GFS; the channel low is less deep. Then the LP Thu 12th is deeper (995mb) and closer (Orkney) with N-lies for Britain generally stronger.

GEM - similar to GFS but both the HP Mon 12th and LP Thu 12th are more strongly developed

GEFS - temps mostly a few degrees above norm to Wed 11th then distinctly cold (as much as 8C below norm) for a week before recovering. Rain 5th-9th (Thu - Mon)  and again from Fri 13th in the S, Scotland misses most of the former period and has less rain in the latter esp in NE. 

Across bits of southern England, anyway. There are two "light rain" symbols here on the MetO automated over the next three days, which is an improvement over yesterday's forecast (none), but... let's just say I'll be pleasantly surprised if we get a soaking.

I've never known so much phantom rain as we've seen this summer with the GFS down here. In the GFS' world it would be a lovely verdant wonderland rather than the parched dustbowl it's become!

(GFS has 12mm of rain here tomorrow, the MetO raw has two hours of light rain, so maybe 3mm?)

I do hope it push further south to keep Epsom dry on Saturday and visit my old work friend in Windsor as it was looking good for those areas before due to inaccurate models once again. 

Mid 20s over Midlands over the Friday to the weekend though. Uppers as high as 15c here but with boy cried wolf many times so hard to get excited this time.

Agreed. If you run the Met Office rain forecast, most of the rain falls south and west of London , to the south coast and all the way down to Cornwall. A bit like channel sliders in the winter, I wouldn't be surprised to see this adjusted further south with time. 

Let hope so as there so little time left to adjust south as tom is Thursday but likely overcast in Epsom to Windsor.

I wouldn't be surprised to see it adjusted, full stop! The predictions for the heaviest rainfall alter day by day, if not hour by hour.

Never ceases to amaze how the fence sitting turns occasional climb down to make solid narratives, only for the reality doing the opposite. 

Talk and hoped of an Indian summer now fade to having to build an ark. 

Show how severe inaccuracies on all forecasts to models are today than in the past which was far more accurate and better before.