model discussion Model output discussion 11th July onwards

[sheikhy]

2 minutes ago, northwestsnow said:

Beautiful runs this evening ..

UKMO looks good....

If ecm looks anyfin like that i will be jumping for joy!!!!!!!not long now!!!!

[Mike Poole]

22 minutes ago, northwestsnow said:

Beautiful runs this evening ..

UKMO looks good....

Yes, very good NWS!  At last.  So often it happens as the schools go back in September.  Even the poorest run of the 12z, has only increasing  potential for settled warm weather at the end, the GEM T240, with WAA: 

Edited September 1, 2021 by Mike Poole

[Guest]

1 hour ago, mb018538 said:

28c Monday on the GFS

27c Tuesday

26c Wednesday 

warmth is widespread too, so loads can enjoy!

Lol not falling into this trap for the 18th time since the start of May. Until the sky is blue and it’s about 21c by 10am theyll be zero trust in models especially gfs given it’s been 100% with cloud amounts everyday this week.

[Mike Poole]

12 minutes ago, Alderc said:

Lol not falling into this trap for the 18th time since the start of May. Until the sky is blue and it’s about 21c by 10am theyll be zero trust in models especially gfs given it’s been 100% with cloud amounts everyday this week.

Aren’t the global models GFS, ECM etc. as rubbish with cloud cover though as they are with precipitation?  They are good for getting the broad synoptic pattern right but local detail isn’t what they are for.  

Anyway, on with the ECM, T120 compared with UKMO and GFS:

ECM between the other two I think, all about the strength of the low by this point.  Caveat to that is ECM looks more likely to ridge over the low and cut it off than GFS because of orientation of the low, maybe?

[mb018538]

ECM also upping the ante tonight and splitting that trough in two. Monday could end up being a hot day at this rate. I mean mid 20s….not that noteworthy in July, but into September it’s on the warm side.

[Mike Poole]

ECM T144, all good:

[Mike Poole]

ECM T168:

Looks a good spell, and nothing to disrupt good weather going forward from here in the longer term.  Good run.

[sheikhy]

Job done what an ecm so far!!!!get ready for some hot sunny weather to make up for the last 10 days of crap!!!

[minus10]

Another good explanation of the 10 day period from the MO and the uncertainties there within. Seems pretty certain it will warm up however uncertainty still in whether warm and dry or warm and wet. Looking promising from the ECM though as stated above....

 

 

[Mike Poole]

ECM T240:

It is not the exact position of the high that is important, it is that the trough is firmly anchored west of us in the Atlantic.  It’s a theme of this evenings runs, but a trend from yesterday’s 12z runs.  And I still think it could shift slightly further west before verification.  

[Methuselah]

It looks like a spell of warmer weather is incoming -- should the GEFS 12Z ensemble be correct? However, as the MetO 10-Day outlook shows -- uncertainty abounds!

    

 

[Eagle Eye]

If only this was at 100 hours then I might believe it because this also has precipitation going onto hit the South soon afterwards.

Edited September 1, 2021 by Eagle Eye

[offerman]

2 hours ago, Alderc said:

Lol not falling into this trap for the 18th time since the start of May. Until the sky is blue and it’s about 21c by 10am theyll be zero trust in models especially gfs given it’s been 100% with cloud amounts everyday this week.

Absolutely spot on post. So many times wrong this summer. 
even this week initially was supposed to be sunny and warm best in the west cold cloudy thank on the East Coast but it seems like the whole of southern England has been like that all week. 
with only Scotland benefiting from warm sunny conditions. 
I saw a video of John Hammond I’m assuming from his home saying categorically no September heatwave whatsoever. temperatures at best might get up into 20 or low 20s at best 

A day later the weather chance have absolutely flipped showing hot weather to come in starting from Saturday. 

even with all their super computers I don’t think these forecast seem to be any better than a decade or two ago. 

not blaming any weather  Presenters or personnel in the offices as I just think you can’t predict nature. The weather will do what the weather wants know Computer will predict it . 

 

[Mike Poole]

ECM cluster T192-T240:

The majority cluster 1 is as we have been discussing.  Cluster 3 also good for a promising September.  The other two go rather off the rails, but not until T216.  All in all very promising output, and not that surprising if you believe like I do, that September is the most reliable month for settled weather.  

[damianslaw]

Theme of 2021 continues... lengthy periods of either dry and fine, or unsettled... each lasting roughly 2-3 weeks apiece.. we are in the dry theme now.

The current high though is notably robust, any reason for this... 

[sheikhy]

Welcome to the party icon 18z!!another massive backtrack from the icon!!!!

[mb018538]

Looking increasingly likely that we will get a 'mini heatwave' of sorts in the early part of next week, before we finally slide into something more unsettled.



Tuesday perhaps looking like the hottest day. 850s up at 17/18c in the south on the UKMO, and very similar on the ECM too. With a southerly flow, we can kiss goodbye to the nuisance low cloud, and if that UKMO chart comes off as shown today, then you'd expect 30c somewhere. GFS (below) going for 28/29c Monday, Tuesday and Wednesday with fairly extensive warmth and some high temperatures:



An ironically late  Autumn hurrah for what has been a disappointing summer in many areas (NW excluded of course).

 

[Guest]

5 minutes ago, mb018538 said:

Looking increasingly likely that we will get a 'mini heatwave' of sorts in the early part of next week, before we finally slide into something more unsettled.



Tuesday perhaps looking like the hottest day. 850s up at 17/18c in the south on the UKMO, and very similar on the ECM too. With a southerly flow, we can kiss goodbye to the nuisance low cloud, and if that UKMO chart comes off as shown today, then you'd expect 30c somewhere. GFS (below) going for 28/29c Monday, Tuesday and Wednesday with fairly extensive warmth and some high temperatures:



An ironically late  Autumn hurrah for what has been a disappointing summer in many areas (NW excluded of course).

 

I’m still not convinced, especially as this weekend now looks like it’ll stay mostly cloudy, still I hope it does warm up however the current forecast is weather trolling of the highest order. Rubbish this weekend, especially given the Bournemouth air show is going ahead, massive potential warm up for 3 days when the kids go back only for it to turn potentially very unsettled later next week and weekend to ruin my golf weekend.  
 

I’m still hoping something like the GEM solution is still on the table later next week, looks much more settled however can’t imagine it will win out against both GFS & ECM. 

[mb018538]

2 minutes ago, Alderc said:

I’m still not convinced, especially as this weekend now looks like it’ll stay mostly cloudy, still I hope it does warm up however the current forecast is weather trolling of the highest order. Rubbish this weekend, especially given the Bournemouth air show is going ahead, massive potential warm up for 3 days when the kids go back only for it to turn potentially very unsettled later next week and weekend to ruin my golf weekend.  
 

I’m still hoping something like the GEM solution is still on the table later next week, looks much more settled however can’t imagine it will win out against both GFS & ECM. 

I wouldn't worry too much about later next week yet - for one big reason! 

TS Larry will soon become major Hurricane Larry - packing 125mph+ winds



FORECAST POSITIONS AND MAX WINDS INIT 02/0300Z 12.8N 30.9W 60 KT 70 MPH 12H 02/1200Z 13.0N 33.3W 70 KT 80 MPH 24H 03/0000Z 13.6N 36.5W 85 KT 100 MPH 36H 03/1200Z 14.2N 39.5W 95 KT 110 MPH 48H 04/0000Z 15.1N 42.2W 100 KT 115 MPH 60H 04/1200Z 16.2N 44.8W 105 KT 120 MPH 72H 05/0000Z 17.4N 47.3W 110 KT 125 MPH 96H 06/0000Z 20.1N 51.4W 110 KT 125 MPH 120H 07/0000Z 22.9N 55.0W 110 KT 125 MPH


Doesn't look like a land strike (thankfully), but it is forecast to head up into the North Atlantic and get scooped by by the jetstream and head in our direction by next weekend. This will cause all sorts of model headaches again, so all bets are off after early next week.

  

[Methuselah]

This morning's GFS 00Z operational run isn't looking too bad at all; whilst heat might be patchy, things look like being on the warm side throughout. Though (as is often the case at this time of year) one must remember to factor in the uncertainty?

    

    

    

And, talk of 'uncertainty' naturally leads us to the GEFS ensembles -- in which the operational and control runs, together with the arithmetic mean, are in general agreement:

    

Edited September 2, 2021 by Ed Stone

[Iceaxecrampon]

Hello.

One week off - what could possibly happen?

[ChannelThunder]

On 01/09/2021 at 22:09, damianslaw said:

Theme of 2021 continues... lengthy periods of either dry and fine, or unsettled... each lasting roughly 2-3 weeks apiece.. we are in the dry theme now.

The current high though is notably robust, any reason for this... 

The reason is known as an Omega Block. You may have heard that term before. It's essentially a big Omega-shaped loop in the jet stream. High pressure gets stuck in the middle of it - in this case that's right over us with all low pressure systems kept at bay to both the east and west of the block. These blocks usually last a good couple of weeks at least, like in this case.

 

[mushymanrob]

On 29/08/2021 at 08:38, mushymanrob said:

Not quite on board for an anticyclonic spell next week. Slight positive pressure over the UK with slight ridging to our east, but quite a moderate upper westerly flow or just south of west. Suggests unsettled, but not overly so. Probably NW/SE split, and overall rather average conditions, or slightly above. lets hope it changes.
 

It has to be said that on this occassion, the Anomaly charts DONT look like being very accurate, its only fair that i flag this up as im quick to do so on the numerous occassions they are accurate.

[sheikhy]

Just now, mushymanrob said:

It has to be said that on this occassion, the Anomaly charts DONT look like being very accurate, its only fair that i flag this up as im quick to do so on the numerous occassions they are accurate.

Was gona mention the post above that you posted a few days ago!!looks wrong but as you say very rarely they are incorrect!!also the anomalies dont take into consideration the hurricanes that could fudge these forecasted anomalies?!!

[Methuselah]

It's good to see the GFS 06Z operational run continue suggesting a warm outlook. Though, it's a tad 'alarming' seeing the chance of a naughty, nasty northerly polluting the tail-end! 

    

    

    

Oh, and, as an aside, today's unrelenting veil of cloud is a little thinner than yesterday's was. 

Edited September 2, 2021 by Ed Stone