Model output discussion - first hot, thundery plume of the summer

[chrisbell-nottheweatherman]

1 hour ago, Ed Stone said:

06Z ensembles:   

                             

So, not exactly great, but not too bad either...Certainly nowt to trigger any Mystic Megian summer 'doomcasts', as yet...?

Dry for the first week or so of July, then lowering pressure and a suggestion of rain, temperatures warm but not too hot - sounds fine to me!

Edited June 27, 2019 by chrisbell-nottheweatherman

[chrisbell-nottheweatherman]

1 hour ago, Ed Stone said:

Well, I did consider commenting on the ensembles for everywhere on the list, but came (after giving it a lot of thought) to the conclusion that the resulting post might be a tad 'long winded'...?

Perhaps a Midlands location might be more acceptable to those in various parts of the country?

[Fourty Point Three Degrees]

44 minutes ago, Quicksilver1989 said:

How does a Mid-Atlantic high in the first week of July dictate the rest of the Summer? There is no evidence that it does.

*IT COULD*

It would help if you re-read before responding. We've seen it many times before the patterns that start setting up for Mid July are OFTEN and SOMETIMES the patterns that determine August. The evidence is in history, Greenland blocks and associated troughs once set up CAN BE hard to move, we got lucky with the early June Greenland high as it shifted a lot quicker before it could intensify. ECM as I mentioned is FI and probably an outlier.

[Interitus]

5 hours ago, Man With Beard said:

You can see just how cold the air is at the 950hpa level - just 7C - which is actually much colder than the North Sea itself at the surface. This air must have originated north of Iceland as that's the only place where the sea is that cold at present, and, with low cloud and no land contact, it's had nothing to warm it. It is only now hitting the warm upper air (if you look at wind charts for 850hpa and 950hpa levels, you can see that they are coming from different directions). 

Why is it assumed that air at 950 hPa, which the charts show is at 640 metres asl hence expectedly colder than the North Sea surface, has originated at sea level thus must be from north of Iceland?

[Derecho]

10 minutes ago, 38.5*C said:

*IT COULD*

It would help if you re-read before responding. We've seen it many times before the patterns that start setting up for Mid July are OFTEN and SOMETIMES the patterns that determine August. The evidence is in history, Greenland blocks and associated troughs once set up CAN BE hard to move, we got lucky with the early June Greenland high as it shifted a lot quicker before it could intensify. ECM as I mentioned is FI and probably an outlier.

In winter there could be some truth in at as high and low pressure systems cover much large areas (for example the winter NAO - the Icelandic low is a prominent feature) but in the Summer steering currents are too weak. You could have a strong Greenland high yet see a heatwave in the UK at the same time if a low pressure system falls to the SW and pressure is high over Europe. It is simply too hard to predict, especially later in the Summer when tropical storms / ex hurricanes can have all sorts of downstream effects.

The only Summer in the last 15 years or so where there was an obvious driver behind the Summer was the persistent westerlies of 2015 due to the North Atlantic cold blob. So I don't think there is anyway next week will have a bearing on the rest of the Summer. 

Edited June 27, 2019 by Quicksilver1989

[nick sussex]

Meteo France red warning now issued for 4 departments in southern France . That’s amazing for heat , very rare to see that .

Temps between 42c and 45 c for tomorrow and Saturday . Thankfully here it’s not expected to get to 40 c , mid to upper thirties which is still hideous but a touch less hot over the weekend .

One of the big problems is some areas of France night time temps have been so high that houses haven’t had a chance to cool down towards the morning .

For heat lovers in the UK it’s more a glancing blow , a bit unlucky or lucky depending on whether you like the heat . The heat can really only shoot north as the high edges east as the flow moves se to south on its western flank .

So Friday into Saturday , se areas more favoured .

Edited June 27, 2019 by nick sussex

[knocker]

Classic sat image at 1330 UTC

[johnholmes]

1 hour ago, Quicksilver1989 said:

In winter there could be some truth in at as high and low pressure systems cover much large areas (for example the winter NAO - the Icelandic low is a prominent feature) but in the Summer steering currents are too weak. You could have a strong Greenland high yet see a heatwave in the UK at the same time if a low pressure system falls to the SW and pressure is high over Europe. It is simply too hard to predict, especially later in the Summer when tropical storms / ex hurricanes can have all sorts of downstream effects.

The only Summer in the last 15 years or so where there was an obvious driver behind the Summer was the persistent westerlies of 2015 due to the North Atlantic cold blob. So I don't think there is anyway next week will have a bearing on the rest of the Summer. 

Quite correct in my view but most know that 38.5 C does tend to try wind ups

[Man With Beard]

1 hour ago, Interitus said:

Why is it assumed that air at 950 hPa, which the charts show is at 640 metres asl hence expectedly colder than the North Sea surface, has originated at sea level thus must be from north of Iceland?

A calculated guess! I won't clutter up the thread with more charts but here are links to charts from earlier in the week that explain my thinking; first, the GFS from Monday 00Z, looking at cloud/precipitation - it's pretty clear the air that is in the North Sea today went through the Iceland region 2 to 3 days ago (you can see this from the cloud movement and the sheering-off from a line of cloud moving between Iceland and Norway as it bends around the high). Upper and lower air was pretty cool at that time, between 0C and 10C except in local spots in Iceland itself.

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=7&heure=0&jour=24&mois=6&annee=2019&archive=1

Now, the EURO4 from 48 hours ago (link below), looking at the 950hpa air temperatures. On Tuesday, North Sea air at this level was 15-20C, well above normal. If you look through the timeframes, you can see an area of 5C working its way from the Faroes down to the North Sea close to Northumberland. Quite a big drop within 24 hours. Highly unlikely that North Sea itself is going to behind all this cooling, since it is at 12C more or less, and highly unlikely to be the air above, which doesn't drop to 5C at any time. It must be down to where the air was coming from.

https://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=euro4&MODELLTYP=1&BASE=201906251200&VAR=t925&HH=24&ARCHIV=0&ZOOM=0&PERIOD=&WMO=

But I'm just an amateur trying to piece things together. I'd more than welcome further input if you have some 

 

 

[Gael_Force]

Look back the archives for the thetaE charts, shows the high coming in off the Atlantic and dragging down the colder 850 temps that were to north of UK.

[MATTWOLVES 3]

Lovely Conditions right now and the next couple of days... But be aware of a sneaky little cold pool coming down from the North end of next week.... Perhaps... Scotland - 4 uppers..... Brace yourselfs... For a bit of skiing in the cairngorms....

[StormChaseUK]

The GFS surface temps are spot on today, 20C here.     Sheltered from NE wind it was 23, 24C in the town.

So if you are in sheltered location you can add, 2C or 3C to the GFS temp I think for tomorrow.

 

[Frosty.]

The Gfs 12z operational is going for highs of upper 20's celsius across a large swathe of england on saturday and around 30c for parts of the SE..perhaps 31c 88f....I think these maxima are undercooked and the SE will see between 32-34c and around 30c for most of england on saturday so hot / humid and sunny for many on saturday but the w / nw becoming cloudier with showery rain, some heavy and thundery which heralds a big drop in temperature from sunday but the s / se mostly escape the rain and stay largely dry. 

[Bristawl Si]

5 minutes ago, I remember Atlantic 252 said:

Vile

Pleasant in any sun

[northwestsnow]

15 minutes ago, I remember Atlantic 252 said:

Vile

Does this not belong in the moaning thread?

By all means post poor looking charts- but you for some reason home in on the worst charts you can find, and then go and slate poor summer sun as a rain ramper  lol.

There are plenty of summery charts to find without going to day 10 11 or 12 ..

Edited June 27, 2019 by northwestsnow

[MATTWOLVES 3]

14 minutes ago, I remember Atlantic 252 said:

Vile

Vile.... 23c and unbroken sun here... Looking at the latest satellite image it's clear for the bulk of England and Wales! 

Edit.... Sorry I got wrong end of the stick, I thought you were referring to today's temps not the 7th of July... A chart at 10 day's out regarding temperature is highly likely to be just a little bit wide of the mark though.. 

 

Edited June 27, 2019 by Mattwolves

[weathermadbarnsleylad]

Don't worry about next week yet. The azores will win out in the end. 

[StormChaseUK]

26 minutes ago, I remember Atlantic 252 said:

Vile

Compared to May/June we have had that;s a gorgeous mildwave   

[northwestsnow]

Just now, weathermadbarnsleylad said:

Don't worry about next week yet. The azores will win out in the end. 

I feel its very finely balanced hand on heart- the blocking across northern latitudes is not going away in a hurry, fascinating model watching at the moment.

 

[knocker]

The gfs 5-10 mean anomaly has the subtropical high amplifying in mid Atlantic with the TPV in close attendance in the NE with an obvious pathway south

[chrisbell-nottheweatherman]

Just now, knocker said:

The gfs 5-10 mean anomaly has the subtropical high amplifying in mid Atlantic with the TPV in close attendance in the NE with an obvious pathway south

Could the vortex lobe link-up with the cut-off low heights near the Azores if it were to head south, do you think?

[Methuselah]

All looks very benign, to me, with an almost total lack of any definitive weather systems; at least, very little in the way of steep pressure gradients?

  

[knocker]

12 minutes ago, chrisbell-nottheweatherman said:

Could the vortex lobe link-up with the cut-off low heights near the Azores if it were to head south, do you think?

Yes I'm afraid I wasn't clear. I meant a pathway for a trough linking the two

[knocker]

5 minutes ago, knocker said:

Yes I'm afraid I wasn't clear. I meant a pathway for a trough linking the two

Rather like this but this is just academic

[MATTWOLVES 3]

Not a bad Gem out to day 8/9

High pressure looks in control especially further south. Temps not bad at all... 34-35 on the cards for the SE on Saturday... Enjoy it if you can!