Model Output Discussion - Mid Summer Onwards

[alexisj9]

2 minutes ago, Sun Chaser said:

2011 record within sight! Mid twenties looks likely to be widespread but I wonder if on the day it could be even higher... the GFS does like to underestimate sometimes.

Just can't believe my eyes anymore, I'll remember this year for many years I think. I'm hoping next year will be more normal.

[MattStoke]

11 minutes ago, Sun Chaser said:

2011 record within sight! Mid twenties looks likely to be widespread but I wonder if on the day it could be even higher... the GFS does like to underestimate sometimes.

From the 16°C/17°C uppers on the GFS, 26/27°C 2m temperatures seems reasonable at this time of year depending on cloud cover, wind direction etc. 

ECM has 850hpa as high as 19°C/20°C, so 2m could go even higher if that model is closer to the mark.

Edited October 1, 2023 by MattStoke

[Weather Enthusiast91]

Meh.. unseasonably warm weather so late in the year just doesn't appeal to me like it would if it was to happen during July or August. I feel the exact same way about unseasonably cold weather from late March onwards.

I don't suppose there's anything more seasonal being shown on any of the models just yet is there? I don't necessarily mean constant wind and rain (though a good named storm would be nice for a day or so), but it would be nice to have a sunny day in the early to mid teens and some cool foggy nights with a touch of frost. But it seems as if it's either one or the other these days, with little in the way of a middle ground.

Edited October 1, 2023 by Weather Enthusiast91

[Metwatch]

2 hours ago, ANYWEATHER said:

You'll be sick of Jack Frost by the end of Winter and Spring

More likely that the majority will be fed up of the persistent rain and lack of sunshine this winter than too much frost and snow! 

Another December 2015 or January 2007 comes and it would be the case of mudmans, not snowmans

[markyo]

28 minutes ago, Sun Chaser said:

2011 record within sight! Mid twenties looks likely to be widespread but I wonder if on the day it could be even higher... the GFS does like to underestimate sometimes.

Very worrying. Totally unseasonal and sad proof in the shift in our climate.

[MP-R]

1 hour ago, alexisj9 said:

To me the temps being so warm to spite so much cloud being about is what has made this year something interesting, not in a good way.

Interesting in the most boring way possible… 

At least we may land a sunnier warm spell next weekend if things don’t change too much between now and then. Tuesday might also see a sunnier interlude.

[WYorksWeather]

16 minutes ago, Sun Chaser said:

2011 record within sight! Mid twenties looks likely to be widespread but I wonder if on the day it could be even higher... the GFS does like to underestimate sometimes.

Based on the experience of the September heatwave, I remember the initial temperature estimates were slightly underdone, with lots of models initially restricting temperatures to the 28-31C range, and in the end we hit 33C.

Interestingly having a look at the GFS the warmth is also trending towards sticking around longer, with maxes for S/S/M/T of 23/26/26/24.

In terms of comparisons, I think anything around the 28/29C range would be equally as impressive as 2011 in relative terms, because we've lost 25 minutes of daylight by the 8th compared to the 1st. But hitting that will still require the right surface conditions.

[Addicks Fan 1981]

Pretty dry really and little if any sign of any rain whatsoever according to the EPS at 240 hours ahead.    

EPS-fast Model – 500mb Height Anomaly for Northern Hemisphere | Tropical Tidbits

WWW.TROPICALTIDBITS.COM

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EPS-fast model forecast of 500mb Height Anomaly for Northern Hemisphere

 

[Cambrian]

In to October, the last quarter of the year, typically a month of temperature transition. In recent years, early October has been like a hangover from the summer, with a lot of residual heat still there to dissipate. Very much the case this year too if we take the ECM extended range forecasts at face value, showing the marked warmth steadily ebbing away. 

Here are the temperature anomaly charts for the next four weeks, week 1 starting tomorrow, temperatures over Europe slowly returning to closer to average as we go through the month. 

   

The anomalously cold temperatures over Scandinavia and the part of the Arctic directly to our north are interesting, these being maintained by a persistent Scandinavian trough drawing cold air south from the pole.

The anomalously high temperatures on the far side of the Arctic to the north of the Bering Sea and over Arctic Canada appear to be due to a combination of Asian warmth being channeled north along the western edge of the central Asian ridge; and in the early part of the month in particular, North American warmth moving north out of eastern Canada up the western side of the east Canada / Greenland ridge. Heights anomalies for weeks 1-3.

  

Once the European heights subside during week 2, Atlantic blocking would appear to be the main influence for the UK and Ireland. On the eastern flank of the Atlantic ridge we’ll likely enjoy a relatively quiet few weeks, the North America / Atlantic / Europe zone looking very meridional, and even more so by week 3. 

The 0z ECM ensemble mean at day 10 shows no real life yet in the PV and the Northern Hemisphere being held in a triple omega pattern. That could be hard to shift. 

 

It looks like we could well have some very pleasant days well into the month. On the other hand, I don’t think that this is being fittingly reflected in the models yet, but chilly nights look increasingly likely too. 

More so if the Atlantic ridge becomes more amplified at times, bringing a sharper flow from the north, tapping into that cold pool with a flow down the eastern side of the high is a possibility.

Admittedly speculative at this stage, but if this happens, temperatures could take quite the tumble in a couple of weeks time as the nights draw in - quiet, foggy weather could well be on the cards, as the last burst of warmth gives way to a much more seasonal period. 

[summer blizzard]

The interesting question after the horrific heatwave to come is what happens next, it looks like a high in the Atlantic will have influence from around day 8..

Disagreement on the pacing leads to quite different outcomes. 

[damianslaw]

3 hours ago, ANYWEATHER said:

Well,well, gfs has gone all messy from its previous runs and Ecm has moved towards gfs  yesterdays  runs .......The roller coaster ride has more twists than usual...!

As often the case, when ECM and GFS offer opposite synoptics at the 144-168 hr timeframe, we then tend to see a coming together, where one nudges closer to the other, whilst the other nudges a bit closer to the one that perhaps had it wrong.

In this case, GFS has swung much more to ECM, with ECM nudging a bit to GFS.

End result a warm pattern still for next weekend, similiar to today is what I expect will be the final outcome. 2 very mild Sunday's. Whether we draw in a cloudy south westerly or drier southetly remains to be seen. 

Longer term, perhaps more uncertainty creeping in, but still signs for heights to build to the NW, but also heights lingering to the SE. 

[Mike Poole]

38 minutes ago, damianslaw said:

As often the case, when ECM and GFS offer opposite synoptics at the 144-168 hr timeframe, we then tend to see a coming together, where one nudges closer to the other, whilst the other nudges a bit closer to the one that perhaps had it wrong.

In this case, GFS has swung much more to ECM, with ECM nudging a bit to GFS.

End result a warm pattern still for next weekend, similiar to today is what I expect will be the final outcome. 2 very mild Sunday's. Whether we draw in a cloudy south westerly or drier southetly remains to be seen. 

Longer term, perhaps more uncertainty creeping in, but still signs for heights to build to the NW, but also heights lingering to the SE. 

Often when we have these standoffs re amount of amplification, with ECM the more amplified, GFS flatter, what ends up verifying is a 2/3 ECM 1/3 GFS blend - and that now looks about where we are headed for next weekend.

Beyond that, I note the GFS 6z FI is largely a UK high, which is different to previous options with a big Atlantic ridge, so yes, uncertainty is high in this period.

[MattStoke]

First of the 12zs, the ICON, looking warmer than previous runs for next weekend. A more prolonged setup, too. It’s a cannon fodder model but good to have it on board.

 

[Mark wheeler]

18 minutes ago, MattStoke said:

First of the 12zs, the ICON, looking warmer than previous runs for next weekend. A more prolonged setup, too. It’s a cannon fodder model but good to have it on board.

 

Yes and similar to last nights Ecm ,  

Last nights ECM below for comparison.

Edited October 1, 2023 by Mark wheeler

[Don]

4 hours ago, alexisj9 said:

Just can't believe my eyes anymore, I'll remember this year for many years I think. I'm hoping next year will be more normal.

Depends what you define as normal?!  However, going by what I think you mean, I doubt it!

4 hours ago, markyo said:

Very worrying. Totally unseasonal and sad proof in the shift in our climate.

Yes, however, don't forget the 8th October 1995 had similar temperatures and I think around mid October 2001, temperatures of 25C were recorded?  That said, there is no doubt our climate has shifted markedly in recent years!

[MattStoke]

18 minutes ago, Mark wheeler said:

Yes and similar to last nights Ecm ,  

Last nights ECM below for comparison.

Looks like the GFS is continuing to move that way, too. Egg on face for a certain someone, yet again.

Edited October 1, 2023 by MattStoke

[Mark wheeler]

7 minutes ago, MattStoke said:

Looks like the GFS is continuing to move that way, too. Egg on face for a certain someone, yet again.

The GFS has almost completely gone to the ECM solution now . Yesterdays 12 GFS had the trough dominant  . Interesting to see the other models now and to see what the ECM comes up with now . 

[Mark wheeler]

Its coming home , its coming home , its coming Summers coming home . 
 

in October!!!!.

UKMO 144

Edited October 1, 2023 by Mark wheeler

[MattStoke]

3 minutes ago, Mark wheeler said:

Its coming home , its coming home , its coming Summers coming home . 
 

in October!!!!.

UKMO 144

GEM similar, and warmer than its 6z run. All heading one way, although the GFS does then introduce cooler air from the north into the following week.

Edited October 1, 2023 by MattStoke

[Don]

4 minutes ago, Mark wheeler said:

Its coming home , its coming home , its coming Summers coming home . 
 

in October!!!!.

UKMO 144

I hope I haven't gone too low (13C) with my October guess already?! 

[Mark wheeler]

1 minute ago, MattStoke said:

GEM similar, and warmer than its 6z run. All heading one way, although the GFS does then introduce cooler air from the north into the following week.

Yep Gem joins the bonanza. Appreciate it is not everyones cup of tea at this time of year but really hoping this comes off so our family can enjoy a bbq on sunday to celebrate a birthday.

[legion_quest]

Interesting to see all the models now lining up after their little disagreement.

Not the outcome I was hoping for, worrying heat levels for this time of year, but makes sense really given just how much there is to our South.

It has to go somewhere, and as it gets hotter and hotter in summer in the Med and Africa, heat is just going to be there for us longer and longer every year.  

Edited October 1, 2023 by legion_quest

[MattStoke]

27 minutes ago, Mark wheeler said:

Its coming home , its coming home , its coming Summers coming home . 
 

in October!!!!.

UKMO 144

And it goes on.

ECM looks to have come out on top on this one. Although, can’t say for definite until it happens.

Edited October 1, 2023 by MattStoke

[I remember Atlantic 252]

2 minutes ago, MattStoke said:

And it goes on.

ECM looks to have come out on top on this one. Although, can’t say for definite until it happens.

If I remember though, wasn't GFS, and maybe other models showing similar for today last Sunday? was definitely expecting 25C and sunny today this time last week, GFS underestimated the Atlantic

[MattStoke]

2 minutes ago, I remember Atlantic 252 said:

If I remember though, wasn't GFS, and maybe other models showing similar for today last Sunday? was definitely expecting 25C and sunny today this time last week, GFS underestimated the Atlantic

Can’t say I recall that. This isn’t just one model showing an unseasonably warm weekend, though. It’s pretty unanimous.

Has been a fairly warm weekend. For those not stuck under persistent rain like we are.

Edited October 1, 2023 by MattStoke