Both '76 and '25 are  17.72C on the Hadley CET page. '76 still having the highest average max, but '25 the highest min.

Also of interest is how much colder spring '76 was than spring '25 (by more than 2C!). Had spring this year not been so warm and dry then summer would surely have been a lot greener and not so arid.

All true. I am very glad some rain has come. The Itchen has been normal or close throughout, but we've just returned from a holiday near Tiverton, where the beautiful Exe is just starting to recover.

Delight to see kingfishers and dippers in numbers.

How does such a discrepancy arise, then?

I mean, 1976 is/was the hottest on record for the CET series.

Yet using the methodology reported on the BBC, it's not even in the top 5, and relatively large gap of 0.4c to this year's

Is it simply down to milder nights? (and increased impact of the UHI effect as more and more of the UK is concreted over?)

1976 is not in the top 5 summers for the UK - the UK Temp Series is  based on all weather stations in England, Scotland, N Ireland & Wales.   As opposed to the CET series which is based on just 3 weather stations in England.    Hence the difference.

Ah, OK. I'm still shocked at how much difference there is (and, given 1995 remains the warmest on record for SW Scotland, the western side of Wales, and a large part of NI, and was a cracker - felt much better than 2025 for much of NW England, too), I'm surprised it's not higher on the overall list

This is a handy map showing the hottest summer on record in each different area of the UK:

https://www.metoffice.gov.uk/binaries/content/gallery/metofficegovuk/images/about-us/press-office/release-images/2025/summer-stats/record_map_by_area.jpg 

The 2025 CET has equalled the 1976 record at 17.2°C.

The map shows how 2025 destroyed the previous hottest summers. Look at a comparable map for 2022 (I think that's the right year) and you'll see how it was the hottest summer on record in a much smaller number of areas. 

You can get all these UK, National and Regional variations for many different parameters in tabular format (including average mean temperature) from the Met Office's Regional Download link

https://www.metoffice.gov.uk/research/climate/maps-and-data/uk-and-regional-series 

Not one day above 30c IMBY and a lot of cloud at times, no doubt leading to high min temps.

Looking at the met office data per Lanky's link for NW England/ N Wales, 2025 has the highest mean and min temp but 1976 has the highest max. 2025 is only in 8th place for max temps.

2025 is also outside the top 20 for sunshine

On the other hand 1976 is outside the top 20 for min temps.

Its a bit like the record breaking  CET in May 2024, a warm but cloudy forgettable month.

It's felt unusually warm to me this summer. Several heatwaves and just endlessly warm temps.  Even the poor looking periods synoptically   have been average or above.  We haven't had endless high pressure or wall to wall sunshine just constantly above average air temperatures.

As an indicator, the house has been constantly warm or uncomfortable, usually there would be days when it was 18c-19c inside in the summer and feel a bit chilly at times but not this year.  Very dry too, this continues to present. 

It's 20.8C outside, another warm and sunny day, and it's now a whole three months since the last time it didn't reach 20C here. I suspect that's unprecedented in recent history!

We simply haven't seen a cold day (a cold day for spring, summer or autumn) for months. This morning felt (for 2025) chilly -  a minimum of 10C...Many August 1976 minimums were much lower than that.

That's staggering!

For the summer as a whole, 69% of days reached 20c here which is very high. 

17.72 and it tupped 76 by thousandths.

What would be interesting is to see the 'extended summer' rankings. Ingrid Holford mentioned this previously - May to September temperatures. 1976 wouldn't rank highly with a cool September and I wonder how 2006 and 2023 would do with their warm Septembers but 1989 looks like a contender, as do 1947 and 2016.

Is that confirmed by the UK Met? I missed the announcement TBH. 

I'd agree with both of these.

It's felt like it's been a long summer, but never an exceptional one in terms of prolonged high maxes and sunshine. If it were a graph, it would be very wavy. We definitely had some periods where the temp was maxing in the low 20's, and others where it turned a bit unsettled/wet (we had one in June that was a stinker)

For whatever reason the MetO pretends the CET doesn't exist, at least when it comes to media reporting about temperatures. You'd think as custodians of the longest-running temperature series in the world that they'd give it a mention now and again, but nope - it's always UK wide or the England and Wales series which they quote.

2025 top.

Staggering when you look at the data like that - 8 out of the top 10 hottest summers of the last 366 years are in the last 50 years and 5 of the top ten are in the last 22 years.

Beat 1976 by 1/1000C

17.718 against 17.717 on the basis of CET (max+min)/2

More staggering is that 4 out of the last 5 years (including this year) are the warmest on record. And the top 10 of all time are since 2011