To my northern neighbours suffering from the current heat wave.

I lived in approx 38C with 90% humidity for 20 years, and I have a few pieces of advice.

1. Don't do anything fast that you can do slow.
2. Umbrellas aren't just for rain. They work for sun, too.
3. Sweat is your friend. Drink lots of liquid, eat and drink things that trigger sweating.

4. Cold showers and baths trigger your body to warm up. Room temp showers work best - and don't bother drying off.

@Remittancegirl

Are you sure about those numbers? 38C with 90% humidity is 36.5C wet-bulb.

That is not survivable by a human and sweating does not cool one down at all in such a temperature. Also, according to Wikipedia, the highest recorded wet bulb temperature ever was 36.3C in UAE.

@vriesk Well, I lived in Ho Chi Minh City for two decades. It regularly hits that temperature and in the rainy season the humidity regularly hovers between 80-90

So, I don't know what you want me to say.

Will you get some extra satisfaction by thinking I'm lying to you while you fry?

@Remittancegirl No, I absolutely don't think you're lying or anything like that. 38C dry-bulb is definitely happening in many places, also the humid ones.

Also, your hot-weather advice is very sound and good.

Just that during the peak-temperature hours, the relative humidity is likely even lower than 80% even during the wettests months, as 38C with even 80% is 34.8C, still on the edge of survival for humans. Vietnam is not listed to ever get above 34C in this list: https://en.wikipedia.org/wiki/Wet-bulb_temperature#Heat_waves_with_high_humidity

Wet-bulb temperature - Wikipedia

@vriesk Man, what is your problem? Doubling down even. Just stop embarassing yourself, please.

@Remittancegirl

@svenscholz Can we stop with this?

There is theory - and science - and then there's just living in thick, hot soup for 6 months a year.

And they're fundamentally different things. Which sounds annoying because theory should be absolutely the truth.

Lived experience just exceeds expectations. That's all I'm saying.

@vriesk

@Remittancegirl @svenscholz yeah, that's extreme.

BTW, do fans still help at those temperatures and humidities?

I'm always surprised how big of a difference sitting next to a fan makes in the somewhat less extreme 35C with low humidity, maybe even a bit better (but very localized) than just AC.

@vriesk
Yes, absolutely. They help evaporate sweat, even if just a little, even if they're not cooling you down directly.

I notice that fans really stop helping at about 40. But it never got that hot in Vietnam where I was. But when I was in Cordoba, which is very dry heat, I noticed that fans started to feel like a hair-dryer on hot at 40C. If anything, it made it feel worse.

@svenscholz

@Remittancegirl @svenscholz oh, that's interesting - I would have thought it's the opposite.
@vriesk Logically, it doesn't make sense. If it is very humid, why would a fan pushing humid air help? But every old structure in semi-equatorial countries has old ceiling fans. These people aren't stupid. They have them because they work. Even in the height of the rainy season. @svenscholz