My weather station has been running since May 2009. The highest recorded dew point temperature was recorded yesterday - 23.6°C. That made it pretty uncomfortable despite the air temperature being 33.1°C - 5.6°C below the highest maximum back in July 2022.

Humidity was the big difference. Just 22% in 2022 compared to 52% yesterday.

That makes a huge difference to how hot it feels. Comparable to a sauna when chucking water on the coals reduces the air temperature but raises the humidity making it feel hotter.

We still have some fog or low cloud up here in Cumbria today, so the temperature is not too bad at the moment. I expect it will heat up soon, although we are expected to be at maybe 27C today. Tomorrow it is supposed to be over 30C.

39C in Jersey tomorrow. Max humidity 90%.

Our dehumidifier is filling it's tank every day.

4 minutes ago, martin-w said:

39C in Jersey tomorrow. Max humidity 90%.

Our dehumidifier is filling it's tank every day.

Max humidity will be overnight, not in daytime. I had 88% humidity here this morning at 05:46. It’s now 55%.

3 hours ago, Ray Proudfoot said:

Max humidity will be overnight, not in daytime. I had 88% humidity here this morning at 05:46. It’s now 55%.

My MetOffice app is saying that for 6 in the morning it will be 86%. Dropped a bit..

55% is what our dehumidifier is set to. Inside our cottage it's currently 29C and 60% humidity, in the green on my little monitor.

35C And 41% outside, currently

Edited yesterday at 02:47 PM1 day by martin-w

I've been trying to get friends and family to talk only about temperature and dew point, and just ignore the relative humidity value altogether, as it gets too confusing at such vastly different temperatures. But they're all like "What's that you nerd?"

Like if Singapore and London are perhaps at the exact same temperature today, then sure, comparing relative humidity in the two cities would give you a good indication of how they feel, but otherwise I always prefer to just look at the dewpoint to see how sweaty it is out there.

Anyway, I was shocked and saddened to hear about all the drownings these past few days. I remember one time when I panicked a bit swimming in Florida. I got caught in a really strong rip current. I knew all about them and exactly what to do, it's just I'd never directly experienced one quite like that before. I can comfortably float about on my back and tread water for hours. I might have just taken it as a free ride to the Bahamas. But I did momentarily feel a sense of panic and flailed about a bit. But then calmly swam parallel to the shore and was very soon out of it and easily able to swim back to the beach. I guess it's a bit like a strong narrow jetstream in the air.

1 hour ago, martin-w said:

55% is what our dehumidifier is set to. Inside our cottage it's currently 29C and 60% humidity, in the green on my little monitor.

30.2°C and 52% humidity here inside. Outside it’s 30.8°C and dew point is 20°C. Max was 32.6°C.

Less hot than yesterday but tomorrow is forecast to be higher.

On 6/21/2026 at 4:19 PM, martin-w said:

Apparently there been a surge in homes installing air-con in the UK, just lately. Domestic ownership has doubled in the past few years.

Average relative humidity in Jersey is 81%. 75 to 85% in the UK.

the guy who won the apprentice back in 2025 was right, its a good gig to be in.

BBC News

Apprentice winner Dean Franklin 'not aware' of licence br...

Dean Franklin says he has had the correct licences to run his air conditioning business since 2014.

6 hours ago, martin-w said:

My MetOffice app is saying that for 6 in the morning it will be 86%. Dropped a bit..

55% is what our dehumidifier is set to. Inside our cottage it's currently 29C and 60% humidity, in the green on my little monitor.

35C And 41% outside, currently

Another million kids off school again tomorrow. What a laughing stock we've become. The Australians must think we are bonkers

Edited 21 hours ago21 hr by fluffyflops

9 hours ago, fluffyflops said:

Another million kids off school again tomorrow. What a laughing stock we've become. The Australians must think we are bonkers

Really though? As we've said, there are hotter countries, but in the British Isles we have high humidity and not usually air conditioning. And our buildings are designed to keep us warm not cool..

It’s 1.5°C hotter than this time yesterday and 2.3°C hotter than this time Tuesday.

The 33.1°C set on Tuesday could certainly be breached today. Humidity is a bit lower at 48%.

Rain here, later today. Thunderstorm was predicted but seems to be no longer expected.

5 hours ago, martin-w said:

Really though? As we've said, there are hotter countries, but in the British Isles we have high humidity and not usually air conditioning. And our buildings are designed to keep us warm not cool..

My house was built in 1896 when they knew a thing or two about building houses and thermodynamics.

It’s south facing with natural stone walls about 50cm thick.

It works like a big thermal battery absorbing all the heat during the day keeping the interior cool and lets the heat out at night. Stand on the patio at night after a hot day and you can feel the heat coming off the wall.

I augment that process in extreme heat like this week by closing all windows and curtains during the day and then opening all the windows and doors at night once the outside temperature drops lower.

There’s French doors at the back and a double door at the front so open those up in the evening and a cooling breeze comes through the house.

I’d hate to think what it’s like in a uk new build houses at the moment

38 minutes ago, jon b said:

My house was built in 1896 when they knew a thing or two about building houses and thermodynamics.

Pete Dowson’s house is a similar age. But even he had to admit defeat this week with the room holding his 737 cockpit retaining too much heat to fire up the sim. And that’s with air cond too.

I’m visiting him on Tuesday when it will have cooled off significantly.