Is it hot in here or is it just me?
No, it’s definitely hot! Even the Japanese Meteorological Agency agrees with me! And according to the Japanese Meteorological Agency, or JMA, while the daytime temperatures might be coming down a little bit, the nighttime temperatures at the Tokyo meteorological observatory are hovering around 27.5 degrees Celsius (81.5 degrees Fahrenheit).
In fact, the temperatures stayed high every night for the eight days leading up to July 14, when the report was released. This number might sound high, and it is, representing a 4.4 increase since record-keeping was first started in 1931.
Not only is it miserable and drastically increases chances of heat stroke while sleeping, there’s even a special word in Japanese for these nights when the temperature stays over 25 degrees Celsius: nettaiya, or sweltering night. So, when you walk into work tomorrow morning looking exhausted, you can just tell your co-workers that the nettaiya kept you up.
In the first 20 years of record keeping, the sweltering nights averaged to about 7.55 a year in Tokyo. On the other hand, the last two decades, from 1992 to 2012, have seen an average of 31.9 sweltering nights per years. And, in case you can’t believe your mental calculations, yes, that’s 4.4 times as many of these miserable nettaiya per year.
Anyone tossing and sweating in bed is probably wondering why they’re so miserable right now, and the answer seems to be, according to the JMA, global warming and the effect of urban heat islands. In case you’re not familiar with the term, urban heat islands work something like this: Tokyo has a lot of buildings and concrete, obviously. During the day, those buildings and concrete absorb the heat and hold it in to a much greater degree than plants or just regular dirt would. At night, when other areas would normally be cooling off, the high temperature of the buildings and concrete keeps the temperature of the city up as well. Thus we get endless nettaiya.
And if you think it’s just a matter of being uncomfortable, think again. Already, two elderly men have reportedly died in their sleep due to heat stroke. As the JMA has pointed out, “In comparison to the measures taken in the daytime, people tend to be very negligent when it comes to the heat at night.” The agency asked people to use air conditioners as necessary.
They don’t have to tell us twice! I’m already sucking down a few million liters of water a day, desperately trying to stay cool.
Source: Sankei News

Japan Weather Association creates new words to describe merciless summer heat
Japanese clothing companies adopt fifth “Intense Heat” season because summer is too long
W.T.F. Japan: Top 5 odd ways Japanese people beat the summer heat【Weird Top Five】
10 tips to help you survive the Japanese summer
Blind Tokyo commuter explains the easiest place for him to stand while riding the train
Pikachu brings electric style to brand-new Pokémon G-Shock watch featuring every stater trio
Taco Spaghetti appears in Japan, and our taco fan rushes to try it[Taste test]
Krispy Kreme Japan releases new fruit doughnuts…that taste better cold
Japanese man’s gross conveyor belt sushi social media prank video gets him a 500,000-yen fine
Starbucks Japan reopens Shinkansen platform store after redesigning it for speed
The adorable, delicious joy of the Totoro cream puff gift box[Taste test]
Beautiful new dangling Totoro socks let the Ghibli mascot sway with every step[Photos]
Family Mart Japan installs red-eyed “Monster Wolf” to keep bears away from convenience store
Japan’s Mos Burger goes super-premium for summer with eel burgers that require pre-orders
Japan announces sudden 400-percent increase in visa fees for foreigners entering the country
Japan launches first overnight Shinkansen bullet train between Tokyo and Osaka this summer
Japanese ninja certification exam attracts 131 candidates from Japan and abroad
Japanese sweets brand creates new drinkable Cigare and we’re totally here for it
Starbucks Japan creates special drink bottle bags, adorable stickers for all 47 prefectures[Pics]
Studio Ghibli store Donguri Republic announces opening of first-ever store in America
“Phantom Egg Shop” opens in Japan, with a dozen rare Japanese varieties
Japanese sweets shop sells an ohagi so exquisite it sells out by noon
New Japanese overnight train coming to connect Tokyo with Tohoku in sleep-travel style
Uniqlo reveals third round of massive 100-year-anniversary manga T-shirts for Jump’s Shueisha
Even at twice regular Daiso price, this handy item is still great for summer travel in Japan
New official Ghibli anime food cookbook will teach you how to make Ponyo’s ramen and more
Forget Tokyo go-karts – there’s a new way to sightsee on four wheels in Japan
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Starbucks Japan releases new drinkware and goods for Valentine’s Day
We deeply regret going into this tunnel on our walk in the mountains of Japan
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
Japan reportedly adding Japanese language skill requirement to most common foreigner work visa
Japan’s 5.3 million beautiful Hitachi Nemophila flowers are now in full bloom[Photos]