Back in 2006, Japanese mass media began using the term “guerrilla rainstorm” to describe short localized downpours of over 100 mm of rain per hour that appeared suddenly and unexpectedly.
The phenomenon is thought to be a result of rapid development of cumulonimbus clouds near urban areas caused by a combination of heat islands and local winds. The rainstorms have proven incredibly difficult to predict (hence the name “guerilla”) and are known for causing flash floods in urban areas.
The photo you see above is of one such guerrilla rainstorm, taken from Tokyo Skytree on September 1.

Chinese Photoshop Trolls Part 3: This Time It’s Personal
Free Hugs? Uhh…Okay, Says Japan
Fashion Friends: Twitter Proves Almost Every Japanese College Student Wears the Same Exact Outfit
China’s Photoshop Experts Will Fix Your Bad Photos, But Be Careful What You Wish For
Chinese Photoshop Trolling Part 2: Now with 20% More Shirtless Men!
Oozing up From Below, Mysterious Marshmallow-like Substance Covers Nanjing Street
The Ten Most Beautiful Tunnels in the World and Where You Can Find Them
We Made Coca-Cola Transparent and Colorless. It Tastes Like…
Crime of Passion: Three Men Forcibly Deported from Saudi Arabia for Being “Too Handsome”
Disney Villains Clean Up Well, Wow Japan
Real-Life Barbie Gives Her Friends and Family a Makeover, Turns Them into Dolls
Peenzilla Worship! Japan’s Kanamara Festival Coming Up this April!
Chinese Woman on Trial for Killing Man by Squeezing His Scrotum
Chinese Student’s Bicycle Seat Breaks and… Gyah!
Before and After: 31 Startling Images of Plastic Surgery in Korea 【Photo Album】
Cool Japan: Big Data Helps Predict Japan’s Next Big Hits (With Awesome ‘Weather’ Map)
Can you explain this physics-defying photograph?
Tokyo Metro Manner Posters Confuse and Delight Foreign Passengers 【Photo Gallery】
Satisfy a Royal Craving – We Try Ice Cream Fit for an Emperor
Oozing up From Below, Mysterious Marshmallow-like Substance Covers Nanjing Street
Fast Cars, Tree Houses, Anime, and Secret Rooms: Crazy Beautiful Cafes in Tokyo and Yokohama
Original Evangelion Design Portfolio Gives us Ripped Robots, Smiling Shinji, and One Unbelievable Plot Divergence
Before and After: 31 Startling Images of Plastic Surgery in Korea 【Photo Album】
A Super Simple Way to Make Colorful 3D Art!
Scenes from the Trains of Japan: Pigeons, Gas Masks, and Sleeping, Oh the Sleeping
Philip Kendall
Steven Simonitch
Master Blaster
Kay
Michelle Lynn Dinh
Jessica Ocheltree
The Best of the Best of Manga: Shonen Jump’s 20 Best Sellers of All-Time
There’s a Sailor Moon in my Coffee! Photos and Tips From a Japanese Manga Latte Artist