Model Output Discussions 12z 01/06/2017

[Frosty.]

Yes Mark it just goes to show that even though next week is being talked about as cool and changeable / unsettled, the Ecm 12z offers a silver lining..The Azores high might have something to say about next week after all.

Edited July 5, 2017 by Frosty.

[Wildswimmer Pete]

5 minutes ago, Mark wheeler said:

Yes frosty , I like happy endings I know it's just for fun but it's nice to be in a hot spell and then see another one potentially on the horizon.

That blue patch indicating very cold air must be unusual for the height of summer.  I hope it doesn't come our way!  

[Singularity]

So ECM more or less follows GEM... Shame it's at such unreliable range but in general it highlights how simply having a low consolidate near the climatological norm position of around Iceland can really help us out during a period of positive summer AO.

[snowray]

Could turn into a very hot mid July if this is close to the mark.

[Mark wheeler]

9 minutes ago, Singularity said:

So ECM more or less follows GEM... Shame it's at such unreliable range but in general it highlights how simply having a low consolidate near the climatological norm position of around Iceland can really help us out during a period of positive summer AO.

Yes it certainly looks similar it's nice to see 2 models take this route even if it is out at the realms of FI

[Fourty Point Three Degrees]

2 hours ago, Frosty. said:

Absolutely, I was just thinking the same thing, scotland looks to be having a terrible summer, well most of it at least and the models don't show any respite, indeed, it's going to be even worse up there next week and possibly further ahead.

Further ahead models have been showing a rise in HP by the end of month which slowly crosses the country eastwards and the Jet Stream is pushed north.  Met Office updates also been saying a rise in HP by months end.

[knocker]

My thoughts on the positive AO, which after all is merely an index of pressure distribution, is that currently it is not doing us any favours, albeit not disastrously so. I assume the argument is that it locks the cold air safely away to the north but this only really applies providing the interface between the cold/warm air, and thus the strongest thermal gradient, is not too far south. Currently it would appear that it is.

Anyway a quick look at this evening's anomalies which tend to agree with this and the latest det. interpretations.

There is pretty good agreement in the 6-10 range with the key as far as we are concerned the continuing low pressure over N.Canada/NW Greenland with associated ridge SE over Iceland and the ridge in central North America This then maintains a fairly strong upper westerly flow over the central Atlantic curtailing any permanent movement north of the Azores high pressure. This does not mean that Azores will not influence our weather but is just signalling the usual phasing of the warm and cold air and thus intermittent periods of unsettled weather with the usual north south bias in these situations. The det. runs will of course determine the detail of this in due course. Temps will be tending below average.

No significant change in the later period

 

Edited July 5, 2017 by knocker

[Kentspur]

1 hour ago, Mark wheeler said:

Yes frosty , I like happy endings I know it's just for fun but it's nice to be in a hot spell and then see another one potentially on the horizon.

Don't forget my birthday 15th July is the famous St Swithun's Day- always determines the weather for the rest of summer only ever seen rain once on 15/07! And yes it was a very wet summer after

[mb018538]

As much as the ecm operational run holds great hope tonight, knockers post above shows that In reality it's a black sheep amongst the data. The means and anomalies all point elsewhere, and the OP run doesn't match the averages. It'll most likely be showing more unsettled after again by the morning!

[knocker]

Actually I'm having trouble finding what is so significant about the det run There is a depression slap bang over us mid week and a large low pressure area to the NW suppressing the transient ridge at the end. Pretty much what you would expect if the forecast pattern is any where near correct.

 

Edited July 5, 2017 by knocker

[ANYWEATHER]

11 minutes ago, mb018538 said:

As much as the ecm operational run holds great hope tonight, knockers post above shows that In reality it's a black sheep amongst the data. The means and anomalies all point elsewhere, and the OP run doesn't match the averages. It'll most likely be showing more unsettled after again by the morning!

Hi would not believe that Knocker  A 1975 Summer coming up

[mb018538]

I'd say the 12z op offers some respite, as between 216-240 when the high builds across the south, low pressure is tracking NE away from the UK. Not that it would lead to anything long lasting, but the GFS in comparison looks vile! Any crumb of comfort is worth a look! 

[mushymanrob]

12 hours ago, snowray said:

It makes no difference Karl if its Summer or Winter, the models still don't have a clue past day 5, just an idea of what might be.

thats simply not true...... the models certainly DO 'have a clue' past day 5, especially the anomaly charts whichever suite you chose.

[mushymanrob]

10 hours ago, knocker said:

My thoughts on the positive AO, which after all is merely an index of pressure distribution, is that currently it is not doing us any favours, albeit not disastrously so. I assume the argument is that it locks the cold air safely away to the north but this only really applies providing the interface between the cold/warm air, and thus the strongest thermal gradient, is not too far south. Currently it would appear that it is.

Anyway a quick look at this evening's anomalies which tend to agree with this and the latest det. interpretations.

There is pretty good agreement in the 6-10 range with the key as far as we are concerned the continuing low pressure over N.Canada/NW Greenland with associated ridge SE over Iceland and the ridge in central North America This then maintains a fairly strong upper westerly flow over the central Atlantic curtailing any permanent movement north of the Azores high pressure. This does not mean that Azores will not influence our weather but is just signalling the usual phasing of the warm and cold air and thus intermittent periods of unsettled weather with the usual north south bias in these situations. The det. runs will of course determine the detail of this in due course. Temps will be tending below average.

No significant change in the later period

 

 yep, and thats bad news for those of us hoping for more settled sunny heat... theres nothing apparent through the mid month period , we will have to wait until the end of the month, at least, for any lengthy settled spell with heat.

[mushymanrob]

11 hours ago, Wildswimmer Pete said:

That blue patch indicating very cold air must be unusual for the height of summer.  I hope it doesn't come our way!  

its not temperature, its air thickness?..

[mb018538]

16 minutes ago, mushymanrob said:

its not temperature, its air thickness?..

Yeah the 500mb charts aren't indicative of temperature. otherwise cracking winter charts like this would be appear to be mild!

 

Back to this morning output. Not much change at all, lower pressure towards the NW, higher pressure towards the SE. Temperatures close to average, no sign of any lasting settled weather or heat at present.

[Gael_Force]

10 hours ago, mb018538 said:

As much as the ecm operational run holds great hope tonight, knockers post above shows that In reality it's a black sheep amongst the data. The means and anomalies all point elsewhere, and the OP run doesn't match the averages. It'll most likely be showing more unsettled after again by the morning!

The next run shows the progression and illustrates the point Knocker was making about the ridge/trough progression in a mobile westerly.

  

[weep]

12 minutes ago, Gael_Force said:

The next run shows the progression and illustrates the point Knocker was making about the ridge/trough progression in a mobile westerly.

  

 

For me the largest difference in this morning's run happens already around Wednesday where see stronger ridge formation.

Edited July 6, 2017 by weep

[Man With Beard]

Strong agreement on the ensembles, both on the means and within the GEFS clusters that we can see too

  

Very hard to get a heatwave out of that. WNW flow, no build of heights over Europe, so little opportunity for air to move up from the south. The south has fluked it this week but very unlikely to be repeated on charts such as these.

On the other hand, though, NW sourced air can sometimes be quite clear, especially the further south and east one goes (where have we heard that before!!). So given the time of the year, I would guess low 20sC for most of England with only the odd bad day, so reasonable summer weather here next week. A bit cooler in the Wales, N England, N Ireland and in Scotland and rather more changeable. 

[Frosty.]

A very warm or hot and humid day today across most of England and Wales with hot spells of sunshine but with scattered heavy showers and thunderstorms breaking out this afternoon and rumbling on through this evening before dying out tonight. Some severe storms with flash flooding and large hail is likely. Looking ahead, more very warm sunny weather to come further south-east but gradually becoming cooler and fresher further north-west with changeable showery conditions but with some sunshine too, noticeably fresher in the SE from sunday joining the rest of the uk. 

Edited July 6, 2017 by Frosty.

[knocker]

Not much change from the EPS this morning And here currently a temp of 16C with fog and sky obscured

Edited July 6, 2017 by knocker

[Frosty.]

Just looking at the Gfs 12z for next week and whilst it is changeable and cooler with some rain and showers there is also some drier periods with sunny spells and pleasant temperatures too, especially further south and east..and high pressure then builds in from the w / sw later next week.  

 

Edited July 6, 2017 by Frosty.

[Mark wheeler]

10 minutes ago, Frosty. said:

Just looking at the Gfs 12z for next week and whilst it is changeable and cooler with some rain and showers there is also some drier periods with sunny spells and pleasant temperatures too, especially further south and east..and high pressure then builds in from the w / sw later next week.  

 

Agreed Frosty not a bad GFS run with the Azores nudging in slightly at times .

[Frosty.]

Week 2 is also an improvement on yesterday's Gfs 12z for England and Wales with increasing atlantic / azores high influence, still very cool and changeable for scotland but eventually..even scotland starts to settle down by the end of the run and become less cool but most of northern Britain is having a dismal summer so far compared to further south, hope things improve for them and we can have a nationwide summery spell!

[phil nw.]

A number of off topic post discussing today's storms forecast etc have been moved to here

A reminder to stick to model discussion only in here please all,Thanks.