Model Output Discussion - The Start Of Summer

[mushymanrob]

1 minute ago, matty007 said:

It's a good point and you are obviosuly more knowledegeable than myself. I am simply going by experience that GFS can sometimes hugely undercook temps. I would say that even with the influence of the northerly winds, surely the temps would be much higher than predicted with uppers such as these?

What sort of temps would we be looking at with a southerly flow and these uppers?

oh its a bitter lesson i learned recently..

records would be under threat for sure, but as ive found out to my cost, you cannot always determine surface temps by viewing the uppers... its true the uppers are a good guide and possibly 9/10 times be near or near as damnit, but not everytime.

[matty007]

3 minutes ago, mushymanrob said:

oh its a bitter lesson i learned recently..

records would be under threat for sure, but as ive found out to my cost, you cannot always determine surface temps by viewing the uppers... its true the uppers are a good guide and possibly 9/10 times be near or near as damnit, but not everytime.

Thanks for letting me know. Always like learning new things.

I have a very good feeling about this plume but it would be such a shame if the winds etc didn't fall right and dampened it. I mean, how often do we get the 20c-25c isothern in the UK? Hardly ever.

Edited June 23, 2019 by matty007

[Frosty.]

The Ecm 0z ensemble mean is plumetastic later in the week..next weekend is very warm / hot..run ends with azores ridge building NE across the uk!!! ..Fan - Tastic!!

Edited June 23, 2019 by Jon Snow

[northwestsnow]

Just now, Jon Snow said:

The Ecm 0z ensemble mean is plumetastic later in the week..next weekend is very warm / hot..run ends with azores ridge building NE across the uk!!!

Its an excellent EC mean Karl   

A warm end to June/beginning of July is looking favourite now- 

A moderation in temps likely but a dry theme beckons with the Azores high in or around the UK..

[NApplewhite]

14 minutes ago, matty007 said:

Thanks for letting me know. Always like learning new things.

I have a very good feeling about this plume but it would be such a shame if the winds etc didn't fall right and dampened it. I mean, how often do we get the 20c-25c isothern in the UK? Hardly ever.

I knew the surface temps would be downgraded! i posted last Tuesday / Wednesday that GFS was overcooking the temperatures. Temps of 33 at night have been downgraded to 9 on the latest run in London! GFS is very inaccurate. This plume is going to be a non event at the surface.

However i am looking forward to the electrical storms across Wales and England tonight! Could be a spectacular event with torrential rain and many lightning strikes (though it could disrupt travel)

[Djdazzle]

39 minutes ago, NApplewhite said:

I knew the surface temps would be downgraded! i posted last Tuesday / Wednesday that GFS was overcooking the temperatures. Temps of 33 at night have been downgraded to 9 on the latest run in London! GFS is very inaccurate. This plume is going to be a non event at the surface.

However i am looking forward to the electrical storms across Wales and England tonight! Could be a spectacular event with torrential rain and many lightning strikes (though it could disrupt travel)

Plume a non event when there is a chance that the June record will go Fri / Sat?

 

Edited June 23, 2019 by Norrance
Sniping

[Methuselah]

One has to say that the GEFS 00Z ensembles have taken a bit of a 'downturn', this morning...More runs needed?

  

  

Not one 30C max shown for London, now...I do hope the 00Z is a aberration!

[bluearmy]

Just now, NApplewhite said:

I knew the surface temps would be downgraded! i posted last Tuesday / Wednesday that GFS was overcooking the temperatures. Temps of 33 at night have been downgraded to 9 on the latest run in London! GFS is very inaccurate. This plume is going to be a non event at the surface.

However i am looking forward to the electrical storms across Wales and England tonight! Could be a spectacular event with torrential rain and many lightning strikes (though it could disrupt travel)

That’s a brave statement .......

this week was always going to be tricky to resolve with the competing upper features interacting (euro and Atlantic ridge plus cut off low)

the end result is the Atlantic ridge being more relevant and forcing the flow to be more east than south as it pushes against the trough  - hence the first plume fails to gain enough traction - at the outset, there were signs that the second push of plume could be more successful depending on how the cut off low escapes .... next weekend’s plus 20c looks like it will verify but whether the plume manages to sustain long enough to allow sunshine with the high uppers and a s flow is unknown ......they’re  the three factors required to get us close to a record temp. 

[East_England_Stormchaser91]

1 minute ago, NApplewhite said:

I knew the surface temps would be downgraded! i posted last Tuesday / Wednesday that GFS was overcooking the temperatures. Temps of 33 at night have been downgraded to 9 on the latest run in London! GFS is very inaccurate. This plume is going to be a non event at the surface.

However i am looking forward to the electrical storms across Wales and England tonight! Could be a spectacular event with torrential rain and many lightning strikes (though it could disrupt travel)

If we see 3 days of the 20c isotherm, we are looking at low 30’s as a conservative estimate. 

It visited our shores for just one single day back on 1st July 2015, and it caused the July all time record to shatter. What was even more mad, is that it could’ve gone above 37c if it wasn’t for an area of high cloud that suppressed temps slightly at 15:00. 

I’ll say that somewhere, maybe Cheltenham or Bristol area could see the highest temps if an easterly scuppers chances for the E/SE areas. 

[Frosty.]

8 minutes ago, Ed Stone said:

One has to say that the GEFS 00Z ensembles have taken a bit of a 'downturn', this morning...More runs needed?

  

  

Not one 30C max shown for London, now...I do hope the 00Z is a aberration!

Oh I don't know, I wouldn't kick these charts out of bed Ed..hmm that even rhymes!!

[Jayces]

13 minutes ago, NApplewhite said:

This plume is going to be a non event at the surface.

For who? The Antarctic? Let's see how it plays out before we write it off. It's going to get much warmer generally for Western Europe even severe so certainly notable weather, if we get in on the action tensions to be seen as it's been going and changing every day which is exactly how the weather works be it sun, rain, snow, there's always changes and we just need to enjoy what we get when we get it.

 

[Weather Boy]

1 hour ago, Djdazzle said:

But that’s the same with any hot spell with an onshore wind. Nobody is saying it will be 30+ on a coast with an onshore wind. In 1990, west London touched 36C with an easterly wind but the east coast was low 20s.

Quite, and that's exactly what is shown on this temperature chart that someone posted earlier.

36°C at Heathrow and, er, 20°C, maybe only 17° on north Essex/ Suffolk coast!

Incidentally, meto are saying 34° for southern counties later in week. Baffled as to why BBC persist with 25° maxes. Are they expecting a temperature inversion??!! Still, meto reassuring me I'm not going mad.

[Singularity]

So I was thinking about why daytime inversions are rare in summer.

Its surface heating leading to strong vertical mixing of the atmosphere.

Global models can’t truly resolve that process so they estimate it - and this is where a lot of error can arise.

So this could be why I’ve so often seen North Sea influences modelled to affect areas away from the windward coasts quite a bit more than the reality.

Temps should be pegged back a bit, sure, but probably not as much as the models are showing Wed-Fri.

So,it might be valid to add 3-5*C generally to the maximums shown for locations 50+ miles inland of the eastern coasts - largest adjustments furthest west.

 

[Methuselah]

Well, whatever malarkey the GFS 00Z is playing at, the ECM looks a potential beaut!

T120:         T240: 

The models will decide nothing...We'll have to leave that to the weather!

[Tim Bland]

3 minutes ago, Jon Snow said:

Oh I don't know, I wouldn't kick these charts out of bed Ed..hmm that even rhymes!!

I don’t understand why people on here and twitter etc are obsessed with the 850hpa temps. Unless you are 1500m up in a balloon they are irrelevant! Why don’t people concentrate on the T2m temps? I can understand in winter posting them as it is relevant when looking for snow,  but what relevance does it have to us on the ground in summer? Not a dig at you Jon as everyone is doing it ! 

[Djdazzle]

1 minute ago, Tim Bland said:

I don’t understand why people on here and twitter etc are obsessed with the 850hpa temps. Unless you are 1500m up in a balloon they are irrelevant! Why don’t people concentrate on the T2m temps? I can understand in winter posting them as it is relevant when looking for snow,  but what relevance does it have to us on the ground in summer? Not a dig at you Jon as everyone is doing it ! 

Of course they are relevant. You need high uppers to achieve the highest temperatures. Not the be all and end all, but to suggest they have no relevance is blatantly wrong and misleading. No wonder newbies get confused.

[mb018538]

3 minutes ago, Tim Bland said:

I don’t understand why people on here and twitter etc are obsessed with the 850hpa temps. Unless you are 1500m up in a balloon they are irrelevant! Why don’t people concentrate on the T2m temps? I can understand in winter posting them as it is relevant when looking for snow,  but what relevance does it have to us on the ground in summer? Not a dig at you Jon as everyone is doing it ! 

Because you can’t get exceptionally high maximum temperatures without them, hence the obsession. It can get warm to hot with modest 850s, but to get into the upper echelons then 850s around 20c are essential.

[Derecho]

34 minutes ago, East_England_Stormchaser91 said:

If we see 3 days of the 20c isotherm, we are looking at low 30’s as a conservative estimate. 

It visited our shores for just one single day back on 1st July 2015, and it caused the July all time record to shatter. What was even more mad, is that it could’ve gone above 37c if it wasn’t for an area of high cloud that suppressed temps slightly at 15:00. 

I’ll say that somewhere, maybe Cheltenham or Bristol area could see the highest temps if an easterly scuppers chances for the E/SE areas. 

Yes my concern however is that the 20C isotherm is being pushed south with every run however in the reliable timeframe.

I feel T84 - T96 is FI in this pattern and comparing the start of Thursday the really hot air has tediously been pushed back yet again. We have gone from heatwave starting Monday to a spell where Monday - Wednesday won't produce any particularly notable temperatures.

 

If I had to make a prediction of what Friday morning would look like it would be this...

And the wait for real heat goes on for yet another 24 hours. My prediction is that some will still be posting ICON or NAVGEM rogue runs which show some extreme uppers for Monday or something which at that point will be a week after this was initially forecast. It's delays to extremes that are the ultimate warning signs of a forecast going awry and I'm convinced that is what we are seeing with this. However we are overlooking this and focusing on the weekend or the GFS temperature predictions. Failure of the 20C isotherm to reach the UK would put this below June 2000 and June 2017 in terms of intensity so it would represent some climbdown from the ensembles. I can't help but feel cynical about the way this is being modelled.

I'm happy to be wrong and I really hope I am but I can only see something like 33C for London from the remaining dregs of a plume later and nothing close to record breaking here. I do think some other areas in the south west could see some high temperatures but I think our window of opportunity to get something more is slipping. The beast from the east was delayed by only 12 hours from its initial start date that was modelled when it first appeared. This could well be 96 hours....

 

 

 

 

Edited June 23, 2019 by Quicksilver1989

[Summer Sun]

At the peak of the heat on 00Z UKMO it gets to 30c in Hampshire on Friday with temps in the west country widely in the upper 20s

Northern France is absolutely roasting by Friday with 38c in Paris and 40c in western France

Back in the UK and if you want to escape the heat a trip to the east coast might be on order where here it just gets into the mid teens

 

[Stabilo19]

850 temps are consistently being modeled as upper teens/low 20s, but surface temps have been massively watered down for London. 

A few days ago the raw data was suggesting temperatures of 31-33 degrees for London throughout the upcoming week. 

GFS 00Z raw data now suggesting average summer weather of 21-24 degrees for London. 

[Guest]

5 minutes ago, Summer Sun said:

At the peak of the heat on 00Z UKMO it gets to 30c in Hampshire on Friday with temps in the west country widely in the upper 20s

Northern France is absolutely roasting by Friday with 38c in Paris and 40c in western France

Back in the UK and if you want to escape the heat a trip to the east coast might be on order where here it just gets into the mid teens

 

Southampton already jointly holds the June temp record, Gosport, Southampton, Bournemouth, Exeter could get very warm. Incredibly interesting Synoptics.

[snowblizzard]

10 minutes ago, Rascals Revenge said:

Just watched latest bbc live forecast. 25c max for London.  You couldn't make it up. Model failure of epic proportions. 

Ensembles solid on +20c 850's for 2/3 days towards the end of this week.

 Add strong summer sunshine and somewhere in South should reach at least 34c! 

[Mapantz]

Enough of the BBC / MetOffice posts please. There are dedicated threads for it. Thanks.

Edited June 23, 2019 by Mapantz
Typo

[Tim Bland]

14 minutes ago, Djdazzle said:

Of course they are relevant. You need high uppers to achieve the highest temperatures. Not the be all and end all, but to suggest they have no relevance is blatantly wrong and misleading. No wonder newbies get confused.

Agree they are relevant to the bigger picture but the majority of posts over the last few days are just posting 850hpa temps and saying how hot it’s going to be. The majority of these posts do not go on to show the ground temps which are nothing special. 

[Frosty.]

11 minutes ago, Stabilo19 said:

GFS 00Z raw data now suggesting average summer weather of 21-24 degrees for London. 

Just look at that heat in France though..epic!!!!