Model Output Discussion - Autumn arrives

[bluearmy]

22 minutes ago, Snowy L said:

Not much really it's the ECM Vs everyone else. To show the difference, the 06z MOGREPS shows every single member going for the big decline after 5pm in London, half split about 5-7pm, the other half 9-11pm. ECM goes for 2pm, it's completely on its own.

 

 

Ec op seems to drop past 20c in London around 5pm 

i haven’t referenced this Tuesday plume exit (re missing out on records) since Friday as during that day we didn’t see a continuation of corrections forward. 

I can’t see what those mogreps timings are - NW chart gives you an option to set the time and see the member readings 

Edited July 17, 2022 by bluearmy

[sunnijim]

Are these temperature predictions for Monday and Tuesday based on clear blue skies?

Reason I ask is that a considerable cloud sheet has developed in SE London this afternoon,making for a very watery and at times insignificant sun.

Temps have stabilised since 1230pm on this basis at 28c.

[MattStoke]

2 minutes ago, sunnijim said:

Are these temperature predictions for Monday and Tuesday based on clear blue skies?

Reason I ask is that a considerable cloud sheet has developed in SE London this afternoon,making for a very watery and at times insignificant sun.

Temps have stabilised since 1230pm on this basis at 28c.

Numerous locations have reached 30’C. High, thin cloud doesn’t do much to limit temperatures.

Edited July 17, 2022 by MattStoke

[sunnijim]

6 minutes ago, MattStoke said:

Numerous locations have reached 30’C. High, thin cloud doesn’t do much to limit temperatures.

This is a bit more than high thin cloud,we have a cloud sheet at times then the high thin stuff alternating!

I suppose my point would be that if we are chasing cloud around of varying thickness this could make the hot spots more localised under longer sunny periods.

Edited July 17, 2022 by sunnijim

[Frosty.]

Feel free too contradict me, but is this not hot?.seriously guys, this could be a record breaker..I think 42c?..but what do I know…yeah..nothing..Hehe?  

[ribster]

3 minutes ago, sunnijim said:

This is a bit more than high thin cloud,we have a cloud sheet at times then the high thin stuff alternating!

Same here, much more extensive, which fortunately means the house doesn't get baked so much. If this amount of cloud creeps in next couple of days it will suppress temps.

[SunnyPlease]

1 minute ago, jon snow said:

Feel free too contradict me, but is this not hot?.seriously guys, this could be a record breaker..I think 42c?..but what do I know…yeah..nothing..Hehe?  

Could even be 43c tbh with 24c uppers, but anywhere between 41-42c is very possible, which is very very very extraordinary and I don't think would be surpassed for a very long time.

Edited July 17, 2022 by SunnyPlease

[sunnijim]

1 minute ago, ribster said:

Same here, much more extensive, which fortunately means the house doesn't get baked so much. If this amount of cloud creeps in next couple of days it will suppress temps.

Yes,that was my original point,we are not talking whispy cloud here,at times it is significant in thickness.

Are these model predictions based on unbroken sunshine?

I have been around long enough to know high cloud that is thick enough does suppress temperatures.

[nick sussex]

This cloud is associated with those weakening fronts which effected more northern areas earlier .

The flow tomorrow is south se and its clear blue skies across France .

[Guest]

Yep, the ARPEGE shows the difference in cloud cover in the coming few days...

Sunday 15z

 

Monday 15z

 

Tuesday 15z

 

Much more high cloud correctly forecast today. A mix of cirrus and cirrostratus here that is breaking up nicely, allowing us to nudge 30C. Blue skies on the way for many tomorrow, and a lot hotter too. Tuesday clearest and hottest north and east of the approaching low

Edited July 17, 2022 by Steel City Skies

[Frosty.]

I think records will be smashed.. and mashed ….according too the GEFS 6z mean!     

Edited July 17, 2022 by jon snow

[tight isobar]

Things developing across the channel.. the formation of the featured isobaric plots look primed for uk heat accomplishment!! @ records breached for sure.. be an interesting watch this

[danm]

31 minutes ago, sunnijim said:

Are these temperature predictions for Monday and Tuesday based on clear blue skies?

Reason I ask is that a considerable cloud sheet has developed in SE London this afternoon,making for a very watery and at times insignificant sun.

Temps have stabilised since 1230pm on this basis at 28c.

You must be under this very small patch of cloud, so it will clear soon. Nothing but very high level haze here, with non stop sunshine. 30°c as it stands. 

[Cambrian]

1 hour ago, legion_quest said:

Do we have any idea as to why? Is there any specific reason that the jet stream is so weak this summer as opposed to previous? 

Obviously global warming and climate change, but is there anything we can point at in the charts and models to say why this summer is getting so hot? 

I only wish I knew enough to answer that one regarding why it’s getting quite so hot. Some contributors to NW have brilliant knowledge of these underlying climatic drivers. I don’t. 

The models are a simulation of the most likely developments from a particular starting time and setup, and so are in many ways a theoretical development and ‘readout’ of what we already have at any one time. As the baseline setup changes, this impacts further on the subsequent outputs.

I have been extremely impressed with the performance of the models so far this summer in handling what is clearly an exceptional set of drivers and a quickly modifying baseline, the way they have reacted and picked out emerging trends has been brilliant to see. I don’t have a favourite, but hats off to the GFS of late. 

Not everywhere has above average temperatures - this is a temperature anomaly chart for Europe for this afternoon, some parts of Eastern Europe are well below average for the time of year. While Western Europe has a southerly plume and sunshine, Eastern Europe has an airmass sourced from the North Atlantic, cloud and rain. Many a summer it’s the other way round!

  

[mathematician]

36 minutes ago, SunnyPlease said:

Could even be 43c tbh with 24c uppers, but anywhere between 41-42c is very possible, which is very very very extraordinary and I don't think would be surpassed for a very long time.

Next year most likely.

Why only 43. I think we may reach 44. Why not!?!

[sunnijim]

34 minutes ago, nick sussex said:

This cloud is associated with those weakening fronts which effected more northern areas earlier .

The flow tomorrow is south se and its clear blue skies across France .

Good to hear,Thankfully I am on the South Coast for two days ( leaving the smoke this evening) having experienced the record breaker in 2019 in London I'm in no rush to experience it again there!

Happy to chase the record online under a cool 32c according to the met office

Edited July 17, 2022 by sunnijim

[bluearmy]

Mogreps 06z update 

Monday is dropping with higher number and now only 6 runs 35+ (at one point yesterday it was 13)

Tuesday is a full house 37+ 

there seems little appetite to maintain uppers through Wednesday 

[MattStoke]

4 minutes ago, mathematician said:

Next year most likely.

Why only 43. I think we may reach 44. Why not!?!

NAVGEM had 45’C the other day. It’s been waiting all these year’s to get it’s own back on those who mock it’s output

2 minutes ago, bluearmy said:

Mogreps 06z update 

Monday is dropping with higher number and now only 6 runs 35+ (at one point yesterday it was 13)

Tuesday is a full house 37+ 

there seems little appetite to maintain uppers through Wednesday 

Don’t know anything about that model but I’m guessing it has a similar tendency to the ECM to underplay temperatures.

Edited July 17, 2022 by MattStoke

[bluearmy]

6 minutes ago, MattStoke said:

NAVGEM had 45’C the other day. It’s been waiting all these year’s to get it’s own back on those who mock it’s output

Don’t know anything about that model but I’m guessing it has a similar tendency to the ECM to underplay temperatures.

It doesn’t seem to be too shabby for Tuesday. 

in addition, I believe these are temps at 15:00 so I expect there is wriggle room for a couple degrees up which would have one member at 41c  

Ukmo raw is similar in struggling to be to high tomorrow but showing the odd 39 for Tuesday 

Edited July 17, 2022 by bluearmy

[chrisbell-nottheweatherman]

3 hours ago, slater said:

So no breakdown for the east and south east on the latest GFS run for Wednesday ,looks like possibly happening overnight. 

Wednesday night/thursday morning?

[slater]

Unexpected cloud cover  this afternoon which has limited  the temperature to part of Norfolk to 28.5c, Wasn’t expected by any of the charts…Or any chat here…

Edited July 17, 2022 by slater

[MattStoke]

Oh look. A GFS ensemble is showing 40’C on the 25th. How silly

[sheikhy]

8 minutes ago, bluearmy said:

Mogreps 06z update 

Monday is dropping with higher number and now only 6 runs 35+ (at one point yesterday it was 13)

Tuesday is a full house 37+ 

there seems little appetite to maintain uppers through Wednesday 

Is that 37 degrees widely across england?!

[bluearmy]

1 minute ago, sheikhy said:

Is that 37 degrees widely across england?!

Roughly London up through mids and into Yorks 

[bluearmy]

10 minutes ago, chrisbell-nottheweatherman said:

Wednesday night/thursday morning?

I wouldn’t pay too much attention to this until we’ve seen the run repeat and have some support