The ancient, lunar-based koyomi almanac marks the start of autumn with risshū 立秋. When hot weather continues beyond that time, the phenomenon is referred to as zansho 残暑, literally “lingering heat.”
On the Gregorian calendar, this year (2025) risshū arrived on August 7 and will continue until rittō 立冬 (the official beginning of winter) arrives on November 7. No doubt about it, this year zansho reigned well beyond risshū.
Indeed, the heat this year has been brutal, relentless really, throughout Japan since late May. The projected weather report is for continued (dangerously) high temperatures (38-40 C/ 100-104F) through the end of September. And although this year has been record-breaking (as each of the past few years have been — a real climate change wake-up call), truth be told, Japan has endured hot summers from time immemorial.
To manage the oppressive heat, the Japanese engage in what they collectively call nōryō 納涼, ways to “escape the heat.” Activities and events with deep history include uchi mizu (sprinkling water on the ground) and displays of fireworks. More modern gatherings include ビール電車, special reserved trains outfitted for partying (reservations required in advance).
uchi mizu 打水
The practice of sprinkling water on the street (or stones in a garden) is called 打水 uchi mizu.
Sprinkling water has long been associated with purification rituals in many societies. In Japanese culture, uchi mizu is also associated with hospitality — a part of preparing to welcome guests. This custom is thought to have begun in the 16th century with the tea ceremony. The practice of sprinkling water on the ground and garden just before guests arrive persists today.
In addition, the evaporation of water cools the immediate area and uchi mizu is common practice throughout Japan as an antidote to oppressive heat. Throughout Japan there are neighborhood uchi mizu daisaku sen 打水大作戦 events intended to provide cool activities, locally.
firework displays 花火
Displays of fireworks in Japan date back to the Edo period (1603-1868). The first such event that took place in 1733 along the banks of Tokyo’s Sumida River was sponsored by the Shogun, Tokugawa Yoshimune. At that time, many people in both the Kansai region and Edo were dying from famine or disease (smallpox, measles). The pyrotechnic display was held to comfort the spirits of the deceased and pray that those remaining would avoid getting the plague.
Magnificent displays created by pyrotechnic craftsmen known as hanabishi 花火師 were so spectacular fireworks displays became an annual event in Edo and other parts of Japan. During Japan’s hot, humid summer and early autumn, admiring the fantasy of lights became a favorite pastime. Today, hot weather firework festivals are a Japanese seasonal tradition.
Beer Trains ビール電車
The original Beer Train debuted in the summer of 1952 on the Odakyu line, leaving Shinjuku at 5 pm heading for Enoshima along the Pacific coast. This nōryō ressha 納涼列車 afforded riders a chance to quaff beer on the train with plenty of time to stroll along the Enoshima beach before catching the return train, arriving back in Shinjuku at 10:30 pm. The beat-the-heat, beer-along-the-way train remained popular through the 1970’s when it closed the service. There was a brief revival in the 1990’s.
Since that time, other train lines in other parts of Japan have begun offering similar services.
This month’s Kitchen PROJECT includes (cucumber) recipes to keep you cool-as-a-cucumber.
Read my September, 2025 newsletter about escaping the lingering heat.
