The Weather Outlook

Remove ads from site

TimS
  • TimS
  • Advanced Member
13 August 2026 18:21:09
Max and mins today for the 3 CET stations (maxes are provisional):

Rothamsted min 14.0 max 35.2

Pershore college min 16.7 max 37.8

Stonyhurst min 18.2 max 31.2

CET min 16.3 max 34.73

CET mean: 25.52C

Which means CET month to date will be between 19.36 and 19.45C.


Brockley, South East London 30m asl
Bertwhistle
14 August 2026 12:28:59
Close Tim! 16.4 and 35.2 for min and max giving a (rounded) 19.4°C to date. Within your range and spot on your prediction up to Thursday a few days ago.


Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

Gavin D
14 August 2026 12:42:23
Hadley

19.4 to the 13th

3.6c above the 61 to 90 average

2.2c above the 91 to 20 average

Retron
14 August 2026 12:56:02

Close Tim! 16.4 and 35.2 for min and max giving a (rounded) 19.4°C to date. Within your range and spot on your prediction up to Thursday a few days ago.

Originally Posted by: Bertwhistle 

That was the 2nd highest CET max on record, then, beating the 34.8 on the 18th July 2022, but below the 37.3 of the following day. It was easily the hottest CET max for August.


Leysdown, north Kent
Gavin D
15 August 2026 12:18:46
Hadley

19.6 to the 14th

3.9c above the 61 to 90 average

2.4c above the 91 to 20 average

TimS
  • TimS
  • Advanced Member
15 August 2026 15:11:46

Hadley

19.6 to the 14th

3.9c above the 61 to 90 average

2.4c above the 91 to 20 average

Originally Posted by: Gavin D 

Didn’t quite make the 19.7 then. CET should stay relatively elevated until Tuesday, before possibly quite a rapid drop.


Brockley, South East London 30m asl
Bertwhistle
15 August 2026 15:45:03

Didn’t quite make the 19.7 then. CET should stay relatively elevated until Tuesday, before possibly quite a rapid drop.

Originally Posted by: TimS 

What do you reckon Tim? Are we on for a first ever 18°C CET summer?

I think the CET is getting bad coverage elsewhere and there are increasing attempts to make the UK average the focus. Don't mind that, but CET is so long-standing it would be a shame to see it fade into reporting obscurity.

I note the Wiki coverage of this summer does UK & also England as a whole, but no mention of CET.

Our climate in England seems so much more aligned to some continental regions now, it seems that to have a UK as a whole record as the main reference would be as pointless as a NW Europe (France to Norway) record.


Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

TimS
  • TimS
  • Advanced Member
15 August 2026 15:54:19

What do you reckon Tim? Are we on for a first ever 18°C CET summer?

I think the CET is getting bad coverage elsewhere and there are increasing attempts to make the UK average the focus. Don't mind that, but CET is so long-standing it would be a shame to see it fade into reporting obscurity.

I note the Wiki coverage of this summer does UK & also England as a whole, but no mention of CET.

Our climate in England seems so much more aligned to some continental regions now, it seems that to have a UK as a whole record as the main reference would be as pointless as a NW Europe (France to Norway) record.

Originally Posted by: Bertwhistle 

I think, without doing the maths, we need mid-upper 17s in August for a 18C summer, which seems achievable so long as we don’t go really cool in the latter part of the month. 

I agree UK wide hides big regional differences, though CET is a bit unusual too being weighted towards the West. In zonal summers where the warmest places are London, Kent and East Anglia (quite common in Augusts in particular) the CET can look very cool. 


Brockley, South East London 30m asl
Hungry Tiger
15 August 2026 16:25:02

Hadley

19.6 to the 14th

3.9c above the 61 to 90 average

2.4c above the 91 to 20 average

Originally Posted by: Gavin D 

I wonder how much it'll come down after this. 🙂🙂🙂🙂


Gavin S. FRmetS.

TWO Moderator.

Contact the TWO team - [email protected]

South Cambridgeshire. 93 metres or 302.25 feet ASL.



TimS
  • TimS
  • Advanced Member
15 August 2026 17:21:34
Annoyingly low max today in Stonyhurst, and very meh temperatures in the other two compared with the Southermost counties. Warm night though. Today looks as follows:

Rothamsted min 18.2 max 24.6

Pershore college min 15.4 max 24.7

Stonyhurst min 13.3 max 18.3

CET min 15.6 max 22.5

CET mean: 19.06

Which means CET month to date will be between 19.52 and 19.61.


Brockley, South East London 30m asl
TimS
  • TimS
  • Advanced Member
16 August 2026 12:17:14
I’ve done some calcs of what we need for the rest of this month to beat various CET thresholds.

Up to the 14th we have 1,401 degree days so far this summer. The record from 2025 and 1976 is 17.72C, which is 1,630 degree days. 

So to beat the all time record (ie get to 17.73C) the rest of the month needs to get 230.26 degree days, at 13.54C. Odds-on

To hit 18.0C for the summer it’s 255.1 at 15.0C. Very likely.

For 18.5C it’s 300.1 at 17.65C. Not impossible, but a stretch given the outlook

For 19.0C, 347.1 at 20.4C. Impossible. 

My guess would be we end up around 18.1-18.2C for the season. 

EDIT: now 19.6 up to the 15th so up to 1,420.5 degree days. 13.1C for the record. 


Brockley, South East London 30m asl
Gavin D
16 August 2026 12:42:41
Hadley

19.6 to the 15th

3.8c above the 61 to 90 average

2.5c above the 91 to 20 average

Retron
16 August 2026 12:47:24
And we now need just 0.25 to get the warmest year! The heatwave has reduced the target by 0.19C in just four days. Remarkable.

The highest annual mean CET ever recorded was 11.23, which is 1.76 higher than normal.

To beat this record the anomaly must be higher than 0.25 for the remainder of this year.


Leysdown, north Kent
Hungry Tiger
16 August 2026 17:59:50
This time next week we could be below 18.5C. 🙂🙂🙂
Gavin S. FRmetS.

TWO Moderator.

Contact the TWO team - [email protected]

South Cambridgeshire. 93 metres or 302.25 feet ASL.



Gavin D
17 August 2026 12:36:25
Hadley

19.5 to the 16th

3.7c above the 61 to 90 average

2.4c above the 91 to 20 average

TimS
  • TimS
  • Advanced Member
17 August 2026 16:48:58

Hadley

19.5 to the 16th

3.7c above the 61 to 90 average

2.4c above the 91 to 20 average

Originally Posted by: Gavin D 

Summer degree days now 1,438.

Run rate for record summer: 12.8C

For 18.0C summer: 14.54

For 18.5C summer: 17.54


Brockley, South East London 30m asl
Chidog
17 August 2026 20:00:00
Looking like a CET close to 20C today to push that required rate still lower
Rob K
18 August 2026 09:05:48
Looking at the daily CET chart I think we have had a new daily CET record every single month since February? https://www.metoffice.gov.uk/hadobs/hadcet/graphs/2026/daily_meantemp_cet_2026.png


Yateley, NE Hampshire, 73m asl

"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome

Bertwhistle
18 August 2026 13:11:45
HadCET still 19.5°C to 17th.
Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

Bertwhistle
18 August 2026 13:13:23

Looking like a CET close to 20C today to push that required rate still lower

Originally Posted by: Chidog 

Correct, 19.8°C yesterday.


Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

Bertwhistle
18 August 2026 13:19:18

Summer degree days now 1,438.

Run rate for record summer: 12.8C

For 18.0C summer: 14.54

For 18.5C summer: 17.54

Originally Posted by: TimS 

I make it 16.2°C for an 18C summer.

31x18=558.

17 x19.5= 331.5 So (558-331.5)÷14 (14 days remaining after 17th) = 16.2 (rounded). It could be a tenth either way depending on our current 19.5 to the 1/100th.


Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

TimS
  • TimS
  • Advanced Member
18 August 2026 13:51:49

I make it 16.2°C for an 18C summer.

31x18=558.

17 x19.5= 331.5 So (558-331.5)÷14 (14 days remaining after 17th) = 16.2 (rounded). It could be a tenth either way depending on our current 19.5 to the 1/100th.

Originally Posted by: Bertwhistle 

That would be for an 18C August wouldn’t it, not an 18C summer?


Brockley, South East London 30m asl
TimS
  • TimS
  • Advanced Member
18 August 2026 13:56:26
So assuming my summer degree days to yesterday were right ((17.4 x 30) + (19.5 x 31) + (19.5 x 16)), we’re now on 1,438 + 19.8 = 1,457.8.

EDIT: just ran the numbers on this evening's GFS op run. We'd just squeeze 18.0C for the summer by the skin of our teeth. August final score 17.55C.

Largely thanks to a lot of cool nights coming up, killing the CET.


Brockley, South East London 30m asl
Bertwhistle
18 August 2026 17:59:13

That would be for an 18C August wouldn’t it, not an 18C summer?

Originally Posted by: TimS 

Totally correct Tim. Should've learned to read!


Bertie, Itchen Valley.

Retire while you can still press the 'retire now' button.

Gavin D
19 August 2026 13:10:06
Hadley

19.5 to the 18th

3.7c above the 61 to 90 average

2.5c above the 91 to 20 average

Remove ads from site