GFS 6z more into line with the ECM evolution, so sort of agreement.

#fingerscrossed

 

12z GFS continues the theme.

GEM lobs a big fat fly into the ointment, mind

(sets up a brilliant weekend for the south, though, with a very plumey looking set-up, then extends that northwards through Sunday to central/eastern UK; western UK more affected by a dirty low that sets up residence to the west of Ireland before inching over the UK to spread its filth)

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Warming up and drying up from the S (though some potential thundery rain over France week 2)

jet - loops around the UK to Mon 16th (rather conflicts with MetO forecast of fine weather this week) then stands off to the N allowing HP to develop over UK until end of run Thu 26th when new streak aimed directly at England.

FAX - LP in Atlantic eventually runs NE-wards across Hebrides 1002 mb Fri 13th with another LP in SW approaches 1010mb Sat 14th. A mess of fronts everywhere.

GFS Op makes more of the LP Sat 14th and runs it up to  Scotland Sun 15th 995 mb; then a general rise of pressure 1030mb widely by Wed 18th. This persists despite close approaches of LP from the S Fri 20th and from the NW Thu 26th (the latter looks as if it might take over)

GEFS - above norm Fri 13th, below Mon 16th, then mean stays near norm with wide scatter (but Op noticeably bullish 7 or 8 C above norm for rest of period to 26th). Very little rain in S, rather more from time to time in N. 

ECM - the weekend's LP approaches more from the W than the SW and is slower to fill and clear away, but the pattern is similar to GFS

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GFS op is very good from day 8 but it's it's a bit of an outlier.

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GFS op is very good from day 8 but it's it's a bit of an outlier.

Yes, good Op runs today. Ensembles less so but the trend is reasonable for the middle third of August and perhaps beyond. 

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Yes, good Op runs today. Ensembles less so but the trend is reasonable for the middle third of August and perhaps beyond. 

 

Agreed. Not heatwave stuff, but dry and settled for most.

 

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Summaries looking steadily warmer and for the SE at least becoming very dry week 2

GFS Op - LP anchored near N Scotland with small secondary drifting up from sW to N England Sat 14th. Pressure begins to rise but unlike yesterday only over Scotland with new LP from France 1000mb SE England Fri 20th, more general rise in pressure from Mon 23rd to cover all of UK by Wed 25th. Traces of an ex-hurricane showing in mid-Atlantic at this time but not coming close.

GEFS - warm to Mon 16th (more like norm in N), cool to Mon 23rd, then erratically warm. Some rain around Fri 20th in S, more like Mon 16th in N

ECM - shows the more general rise in pressure starting Mon 16th but only slowly creeping in from SW with a spell of N/NW winds on its flank

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UM is interesting. Very warm uppers coming across the Atlantic.

 

 

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UM is interesting. Very warm uppers coming across the Atlantic.

No doubt converting to low cloud and drizzle by the time it arrives in Western Scotland 

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The latest GFS Ops reverts back to the 'faux settled weather' we had earlier in the summer. Pressure generally high but with nasty little depressions popping up and potentially ruining people's outdoor plans.
Having 2 bbqs planned for this week, I was hoping for a dry weekend at least. The latest fax charts for Sunday show depressions north, south and west of us!

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UM is interesting. Very warm uppers coming across the Atlantic.

 

 

 

 

Looks like it's an area of hot air moving around a large AH and not being overly modified?

GFS & ECM have a similarish evolution, although with less warm uppers.

 

I'd love it to come off! (although without the low cloud a drizzle that GezM merrily suggested ) 

 

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I can remember one or two occasions in my lifetime where we've had a hot NW wind coming round an Atlantic High with north-eastern areas reaching 28 C with lenticular clouds over the mountains and low cloud in the west

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Looks like it's an area of hot air moving around a large AH and not being overly modified?

GFS & ECM have a similarish evolution, although with less warm uppers.

 

I'd love it to come off! (although without the low cloud a drizzle that GezM merrily suggested ) 

 

Warm uppers coming in from the N. Atlantic like that only spell one thing for those of us exposed to the W/NW flow:

And with a sickening humidity to it as well. 

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Now you see it, now you don't! Complete switch in wx summaries since yesterday showing cooler weather for all and much wetter for England in week 2, quite contrary to previous forecast.

Jet currently running W-E across UK, switches to N-S Tue 17th, and then fades for a few days before enclosing UK in a loop Sun 22nd. W-E flow then resumes across England esp strong Fri 27th

GFS Op - LP moving in from Atlantic to N Scotland 1005 mb Sat 14th and a secondary then from SW across Ireland to reinforce the original. HP then builds to W but not close enough to shift the LP, by Tue 17th over Scandinavia, and sticking there to give a spell of N/NW winds to Sat 21st before retrogressing to UK Sun 22nd. New LP brewing on Atlantic then moves in to take over, 990mb SW approaches Sat 28th 

GEFS - temps dropping off to the cool side Mon 16th, staying there to Sun 22nd when most runs are warm enough to lift the mean above norm(but op & control stay cool). A little rain from time to time in S after Mon 16th (Yes, this contradicts the wx above), slightly more in N

ECM - similar to GFS to  Fri 20th when the Scandi LP relaxes its grip and by end of run Sun 22nd strong rise of pressure over Britain , 1025mb in SW

 

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Still no signs of things really settling down in the reliable timeframe. Most places getting some decent weather from time to time. GEFS sees high pressure more dominant in 10 days time but this is at odds with other models and the Met Office long term outlook. I'm not expecting that settled scenario to materialise.

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Still no signs of things really settling down in the reliable timeframe. Most places getting some decent weather from time to time. GEFS sees high pressure more dominant in 10 days time but this is at odds with other models and the Met Office long term outlook. I'm not expecting that settled scenario to materialise.

Not saying you're wrong, but the ECM ENS looks fairly solid mid term. I'd not be surprised to see the UK Met going for a more settled scenario.

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I can remember one or two occasions in my lifetime where we've had a hot NW wind coming round an Atlantic High with north-eastern areas reaching 28 C with lenticular clouds over the mountains and low cloud in the west

It'll be returning tropical maritime airmass, something rarely talked about. The air mass originating in the far subtropics (S of Azores to Caribbean) travelled somewhere to the N then returning SE over UK. It's (obviously) very warm & humid, but cooled to variable extent in lowest layers. The cool layer allows extensive Sc & St clouds to form & cover the W coasts, but over warm E UK can sometimes promote subtle instability in lowest layers. The rTm airmass's true nature is revealed when it is blown over the mountains as Fohn winds, giving unusually high temperatures on the lee side.

 

It'll be returning tropical maritime airmass, something rarely talked about. The air mass originating in the far subtropics (S of Azores to Caribbean) travelled somewhere to the N then returning SE over UK. It's (obviously) very warm & humid, but cooled to variable extent in lowest layers. The cool layer allows extensive Sc & St clouds to form & cover the W coasts, but over warm E UK can sometimes promote subtle instability in lowest layers. The rTm airmass's true nature is revealed when it is blown over the mountains as Fohn winds, giving unusually high temperatures on the lee side.

Yes that's what it looked like. I think today's UM 00z is actually quite similar.

https://www.theweatheroutlook.com/twodata/ukmet.aspx?run=00&charthour=144&chartname=850_temperature&chartregion=na-region&charttag=850hPa%20temp%20C

https://www.theweatheroutlook.com/twodata/ukmet.aspx?run=00&charthour=156&chartname=850_temperature&chartregion=na-region&charttag=850hPa%20temp%20C

https://www.theweatheroutlook.com/twodata/ukmet.aspx?run=00&charthour=168&chartname=850_temperature&chartregion=na-region&charttag=850hPa%20temp%20C

 

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The GEFS are showing quite a big split emerging for the t850s from around the 22nd, the majority going for uppers 10c+ but quite a few still keeping it around the 5c mark.

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Not saying you're wrong, but the ECM ENS looks fairly solid mid term. I'd not be surprised to see the UK Met going for a more settled scenario.

Yes, they are holding firm. And last night's EC run (I haven't looked at this morning's offer) showed potential heatwave conditions becoming established post day 10 once again. 

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Glad to see the Op well below the majority in the GEFS spread. Mean ensemble surface max temps low & occasionally mid twenties through to the end. Some hot outliers.

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