Model Output Discussion - Early Summer and Beyond

[Guest]

1 hour ago, *Stormforce~beka* said:

There is plenty of time for the weather to go tits up for Sunday yet! We aren't that reliable this far out.

GFS doesn't need plenty of time to screw it up, just needs the very next run to make a bigger deals of the trough from the north west and south which now merge to give a showery and cooler Fri-Sun

 

Don't worry through its not just GFS, ICON, GEM & UKMO all suddenly fail to develop pressure enough to prevent rain, heavy at times falling during the Friday to Sunday period. GEM is particularly bad. The GFS Ensemble mean for pressure is down 3mb for the weekend from the 06Z to 12Z, that seems quite a bit move? 

This evenings 12Z runs make an absolutely mockery of both the BBC & Meto forecasts for the weekend I've just watched which both indicated a vastly improved weekend picture and one I think many expected us to bed in.

Can we not just catch a break.....Although to be fair, may be much better up in Scotland. 

Ah just 19 days until the Dominican Republic, no stupid upper trough will get me down there......

Edited May 30, 2022 by Alderc

[Don]

30 minutes ago, Roadrunner said:

Yes indeed and with the family and I coming camping in Winchester over the weekend I for one will be hoping it's dry on Sunday morning when we pack away - nothing worse than packing away in the rain or with a wet tent and having to endure an erection at home. 

Hopefully the weather will stay dry Friday to Sunday, could do with some luck currently!

[Guest]

ECM12Z follows all the other with a much more unsettled weekend, Sunday very similar to GEM and a real howler. 
 

Rain and temps struggling into the low to mid teens. 
 

 

Also more of a trend for things to turn more generally unsettled next week, several of the models bring a relatively deep low pressure in from the Atlantic into the Northwest early next week.

Edited May 30, 2022 by Alderc

[Dangerous55019]

Evening everyone. 

Time for a look at the CFS v2 four weekly anomaly charts, just to see if any of them can help clear the muddy waters a bit... 

Week 1 - 30th May to the 5th June: High pressure appears to be more in the Arctic circle! A trough of low pressure appears to be stretching from the Azores right the way up to southern tip of Norway and Sweden! Yes this does cover us here in the UK. To me this says, the first wave of the 'European Summer Monsoon' as low pressure moves in from the West bringing cooler weather and heavy slow moving showers is bang on cue!

Week 2 - 6th to the 12th June: Again there is a trough of low(er) pressure running from the Bay of Biscay right up to Norway and Sweden. I'm gonna hazard a guess at rinse and repeat of week 1... Which thinking about it is right bang on cue for the second wave of the European summer Monsoon. 

Week 3 - 13th to the 19th June: Low pressure is now more based out to the west of Ireland, and a displaced Azores High covering Portugal, Spain and France would leave us in a potentially moist and humid air flow. Certainly not cold, and the more settled weather towards the southern part of the UK. Meanwhile Ireland and the northern part of the UK could see some more unsettled weather at times.

Week 4 - 20th to the 26th June: The Azores high appears to be expanding out of main land Europe, and covering us here in the UK, as well as Norway, Sweden etc. To me this says fine and settled.


So there you go folks! Sorry if that's not what some of you want to hear or see, but I can only say what the charts are showing.

I'll pop back and do this again to see if anything has altered. 

[Mike Poole]

8 minutes ago, Alderc said:

ECM12Z follows all the other with a much more unsettled weekend, Sunday very similar to GEM and a real howler. 
 

Rain and temps struggling into the low to mid teens. 
 

Apologies, posted in error.

Edited May 30, 2022 by Mike Poole

[mb018538]

9 minutes ago, Alderc said:

ECM12Z follows all the other with a much more unsettled weekend, Sunday very similar to GEM and a real howler. 
 

Rain and temps struggling into the low to mid teens. 
 

 

Also more of a trend for things to turn more generally unsettled next week, several of the models bring a relatively deep low pressure in from the Atlantic into the Northwest early next week.

Just looking like last year all over again. Weak surface highs that do nothing, upper lows wandering around and across the UK and being a nuisance, and northern blocking that won’t collapse.

I was starting to get a bit more optimistic on Friday to Saturday, but it’s been a downhill slide again the last couple of days to the point where no day looks totally dry in the country, plenty of cloud, and there isn’t really any warmth on offer either. After a very dull May I’d quite like some sun! Guess we will have to wait.

[Roadrunner]

What is odd is the Met / Beeb forecast which one would assume uses data from the 12z suite does not match up to these latest runs. They obviously have access to a lot more data than us so I'm pinning my hopes on that. 

Time's a ticking though for the jubilee... 

[mb018538]

19 minutes ago, Roadrunner said:

What is odd is the Met / Beeb forecast which one would assume uses data from the 12z suite does not match up to these latest runs. They obviously have access to a lot more data than us so I'm pinning my hopes on that. 

Time's a ticking though for the jubilee... 

Pretty sure the BBC uses 00z data. Their 10 day forecast that gets updated in the evening is based on 00z data anyway. Not sure when they switch over to the latest run for their forecast?

[ANYWEATHER]

The 12z suites have Definately had a turn for the worse especially for southern Britain late week into the Jubilee weekend. The high forecast for the weekend was always looking feeble and weak, and tonight's 12z suite has certainly played catch up. Hopefully it won't be as bad as the models now suggest, but there's one thing we can't control and that's the weathef

[Guest]

2 minutes ago, mb018538 said:

Pretty sure the BBC uses 00z data. Their 10 day forecast that gets updated in the evening is based on 00z data anyway. Not sure when they switch over to the latest run for their forecast?

Yeah the forecasts the METO & BBC issued around 15Z were effectively out of date just a couple of hours later. 
 

To be fair on the METO forecast Alex Deakin mentioned there was still uncertainty around the weekend and said there was a chance of a few showers pushing into the south. Not sure they would have expected such a rapid change (again) 

45 minutes ago, mb018538 said:

Just looking like last year all over again. Weak surface highs that do nothing, upper lows wandering around and across the UK and being a nuisance, and northern blocking that won’t collapse.

I was starting to get a bit more optimistic on Friday to Saturday, but it’s been a downhill slide again the last couple of days to the point where no day looks totally dry in the country, plenty of cloud, and there isn’t really any warmth on offer either. After a very dull May I’d quite like some sun! Guess we will have to wait.

Keep thinking about last summer hoping it’s not another, we’ve already had four spells in the 6-10day range where optimism has been replaced with frustration. 

[terrier]

Wow what a turn around this evening in the output. I’m surprised how bullish the beeb were earlier regarding it settling down towards the back end of the week. If models are showing similar tomorrow morning expect a monumental climb down from the met again. Looking like the jubilee weekend will be cloudy cool and wet looking at tonight’s output. 

[Cambrian]

Summer’s nearly upon us. Cool  Just before it arrives, it’s worth reflecting on just how well the models have performed during this last part of spring. Here on the left is the 12z ECM op chart for 72h on 2 June, followed by the 10 day operational run charts from the ECM, GEM and GFS for 2 June from a week ago. 

   

There are naturally a lot of differences, but a mixture of the three might have worked! The main elements are there or thereabouts - the high pressure to the west / northwest making efforts to ridge down over the UK and Ireland, a low pressure pushing along its southern flank (ECM), low pressure over Scandinavia, high pressure over eastern Canada and the Caucasus.

Only the GFS really picked up on the low pressure developing between Greenland and Iceland, an important element in regard of the discussion of northern blocking and it perhaps framing the early summer. By day 5 on today’s ECM this has developed into a bridge between low pressure systems over the eastern seaboard, through Iceland to northern Scandinavia. 

Even if the day 5 / day 10 hemispheric views show plenty of high pressure over higher latitudes, looking across the whole of the North Atlantic, the pressure to the north is consistently lower than that to the south, so it doesn’t appear that this episode of northern blacking will rule our weather for half a week into summer let alone half a season. 

 

With the slowly alternating  patterns of the spring looking to be maintained, however, it wouldn’t be a surprise to see further episodes of proper blocking to the north at times.

For now, the first part of summer looks like a typical picture of high pressure trying to push up from the south and west against low pressure to our north, an overall gentle supply from the west, the pattern oscillating north and south, some cooler days with some rain but many dry warm days too - can’t see it being a spectacularly poor or great start to summer at all, 12z ECM / GFS ops day 8/9, 

 
 

the GFS keener on a more southerly tracked jet stream at times, but the Atlantic lows still getting pushed back north by a consistent build of heights from the south, all feasible outcomes looking forward and nothing exceptional for early June. 

[Snowy L]

How can professional forecasters be so bullish about settled weather when we have so many small lows flying around, especially when the pattern has been for the UK to be a magnet for them the last couple of months. Have they learnt nothing from watching 4 10-day out UK high model predictions collapsing in a row?

Edited May 30, 2022 by Snowy L

[Roadrunner]

22 minutes ago, terrier said:

Wow what a turn around this evening in the output. I’m surprised how bullish the beeb were earlier regarding it settling down towards the back end of the week. If models are showing similar tomorrow morning expect a monumental climb down from the met again. Looking like the jubilee weekend will be cloudy cool and wet looking at tonight’s output. 

That's what puzzles me! They never usually commit so heavily unless they are very sure about a forecast. One last straw to grab is, if things can get worse so quickly they can also get better. Guess it would be boring though living somewhere where you could guarantee good weather for outdoor events or guarantee snow in winter! 

[TwisterGirl81]

5 minutes ago, Snowy L said:

How can professional forecasters be so bullish about settled weather when we have so many small lows flying around, especially when the pattern has been for the UK to be a magnet for them the last couple of months. Have they learnt nothing from watching 4 10-day out UK high model predictions collapsing in a row?

It's only really been one month where the weather hasn't been as dry as it was the previous 4 months which were very dry or am I missing something? and lots of times with high pressure....Really hoping the models flip back to sunny and warm tomorrow...This is the changeable nature of living on an island right by  the Atlantic and gulf stream, fingers crossed

[MATTWOLVES 3]

I sense the Summer is over vultures are getting ready to pounce on here..far too much emotion based around every operational run. Well let me tell you Summer will be over...wait for it...on August 31st...but being as September tends to be a nice month,it could last longer  

Much speculation over Exeter being wrong over these latest forecasts and perhaps there could be a big backtrack from them tomorrow! Not really....there are some uncertainties over showers pushing into the South later this weekend,and there is mention of largely more unsettled conditions next week,before it settles down from the West...beyond that looks pretty good away from the East! Sorry guys I hope it improves for all.

Tonight's mean looks a little more settled than the op run in my eyes,and just looking at the ens shows quite the spread of uncertainty moving forward! So it would be best to take things not to seriously on current data.

All is not lost though...im still.waiting for the torrential showers they've been talking about for the last couple of days.

Wouldn't be at all suprised to see the output looking different again come the morning runs. But hey why worry...summer does not even start til Sunday...and in some people eyes on the 21st of the new month!

So in a nutshell the op runs took a dive this evening...but the mean looks OK,with UNCERTAINTY being the big word moving forward.

A blessed evening to all of you.

[Scorcher]

32 minutes ago, MATTWOLVES said:

I sense the Summer is over vultures are getting ready to pounce on here..far too much emotion based around every operational run. Well let me tell you Summer will be over...wait for it...on August 31st...but being as September tends to be a nice month,it could last longer  

Much speculation over Exeter being wrong over these latest forecasts and perhaps there could be a big backtrack from them tomorrow! Not really....there are some uncertainties over showers pushing into the South later this weekend,and there is mention of largely more unsettled conditions next week,before it settles down from the West...beyond that looks pretty good away from the East! Sorry guys I hope it improves for all.

Tonight's mean looks a little more settled than the op run in my eyes,and just looking at the ens shows quite the spread of uncertainty moving forward! So it would be best to take things not to seriously on current data.

All is not lost though...im still.waiting for the torrential showers they've been talking about for the last couple of days.

Wouldn't be at all suprised to see the output looking different again come the morning runs. But hey why worry...summer does not even start til Sunday...and in some people eyes on the 21st of the new month!

So in a nutshell the op runs took a dive this evening...but the mean looks OK,with UNCERTAINTY being the big word moving forward.

A blessed evening to all of you.

Great Post Matt- couldn't have said it better myself. So many amateur forecasters in here convinced they know more than the Met Office- and this is days before the event has even happened!

Always interesting how certain posters reappear as soon as something seems to be going wrong.

Has anyone considered the fact that the professionals have a lot more data available and years of expertise and training?

[Cheshire Freeze]

2 hours ago, Scorcher said:

Great Post Matt- couldn't have said it better myself. So many amateur forecasters in here convinced they know more than the Met Office- and this is days before the event has even happened!

Always interesting how certain posters reappear as soon as something seems to be going wrong.

Has anyone considered the fact that the professionals have a lot more data available and years of expertise and training?

In this day and age we have access to most of the same charts that many professionals do.

Unlike the pros we can report in real time on here what the modelling shows. The forecasts we see on TV aren't reacting in real time to the latest data, which is why it seems like on occasion they are 24 hours behind the curve.

It's funny because in winter if the pros are going for cold and snow, you are very quick to point out if the models are no longer showing that scenario. Not having a go by the way, it happens when you have a certain weather preference. You dwell on what you personally want to see happen.

Anyhoo, we're in a la nina summer, not sure what people are expecting from it? 'Mixed' will be towards the top end of what we can expect...and there is certainly nothing wrong with that...a bit of something for everyone.

Edited May 31, 2022 by CreweCold

[Guest]

Goodness me, it gets worse, while thursday and Friday May be half decent in the south the actual weekend is heading into washout status in the south. 
 

GFS, GEM and UKMO now have 30-50mm falling quite widely over the weekend with temps struggling to 12-14C on Sunday. I don’t think I can ever recall such a rapid deterioration in model output it’s like an actual nightmare. 
 

 

GFS then goes full blown Atlantic, 3 or 4 deep areas of low pressure swinging in from the west, it’s a shocking run from end to end. 

Edited May 31, 2022 by Alderc

[mountain shadow]

21 minutes ago, Alderc said:

Goodness me, it gets worse, while thursday and Friday May be half decent in the south the actual weekend is heading into washout status in the south. 
 

GFS, GEM and UKMO now have 30-50mm falling quite widely over the weekend with temps struggling to 12-14C on Sunday. I don’t think I can ever recall such a rapid deterioration in model output it’s like an actual nightmare. 
 

 

GFS then goes full blown Atlantic, 3 or 4 deep areas of low pressure swinging in from the west, it’s a shocking run from end to end. 

After the great runs on yesterday's 0z, this is a kick in the teeth.

Yesterday, for County Down, showed Friday as wall to wall sunshine and 20C temps, now it's heavy rain.

 

[Scorcher]

6 hours ago, CreweCold said:

It's funny because in winter if the pros are going for cold and snow, you are very quick to point out if the models are no longer showing that scenario. Not having a go by the way, it happens when you have a certain weather preference. You dwell on what you personally want to see happen.

I think you'll find that's untrue as I hardly ever post in winter or even read the forums. In this case it's mostly people who supposedly want summery conditions, but simply love a moan. It's not celebratory in the slightest.

[mb018538]

Think suffice to say that between Thursday and Monday some areas are going to get absolutely soaked. All will depend on where these little upper features get slowed down or stuck. That’s about all to untangle in this increasingly poor outlook. The only positive being the cooler air of the last couple of days has gone.

[Scorcher]

6 hours ago, CreweCold said:

In this day and age we have access to most of the same charts that many professionals do.

Unlike the pros we can report in real time on here what the modelling shows. The forecasts we see on TV aren't reacting in real time to the latest data, which is why it seems like on occasion they are 24 hours behind the curve.

We don't have access to everything they do- it's absurd to believe we know as much as people who do this for a full time job. And rather disrespectful. The apps and websites do update in real time.

[IDO]

14 minutes ago, Alderc said:

Goodness me, it gets worse, while thursday and Friday May be half decent in the south the actual weekend is heading into washout status in the south. 
 

GFS, GEM and UKMO now have 30-50mm falling quite widely over the weekend with temps struggling to 12-14C on Sunday. I don’t think I can ever recall such a rapid deterioration in model output it’s like an actual nightmare. 
 

 

GFS then goes full blown Atlantic, 3 or 4 deep areas of low pressure swinging in from the west, it’s a shocking run from end to end. 

Some gremlins within the GFS 0z run and the op went off on one very early and is a crazy outlier in temps and more especially rainfall:

So worst case scenario and unlikely. Though looking at the synoptics from Sat-Mon, a cold front moving south/SE, interacting with a low (on GFS op, UKMO further south) and then a cut-off upper low and there is a recipe for unsettled weather in the south. The macro picture is difficult as it is quite a messy quasi-blocked setup.

[Guest]

 

13 minutes ago, mb018538 said:

Think suffice to say that between Thursday and Monday some areas are going to get absolutely soaked. All will depend on where these little upper features get slowed down or stuck. That’s about all to untangle in this increasingly poor outlook. The only positive being the cooler air of the last couple of days has gone.

will be interesting to see how quickly the BBC and METO update their forecasts.