Record-Breaking Early End to Japan’s Rainy Season (Tsuyu) in 2025

Japan’s rainy season, known as tsuyu, typically drenches the country with heavy rainfall and humidity from June to July. However, in an unprecedented and historic event, the Japan Meteorological Agency (JMA) announced on June 27, 2025, that the rainy season ended remarkably early across several western regions. This record-breaking early end has sparked excitement, curiosity, and concern—what does it mean for Japan’s weather, water resources, and daily life?

Official Announcement and Affected Regions

On June 27, 2025, the JMA officially declared the end of the rainy season in southern Kyushu, northern Kyushu, Chugoku, Shikoku, and Kinki regions. Spanning from Kyoto to southern Kyushu, this early end affects a vast swath of western Japan, making it a significant weather event worth watching.

Historic Milestone: Earliest End on Record

For the first time in recorded history, northern Kyushu, Chugoku, Shikoku, and Kinki regions saw the rainy season wrap up in June—an anomaly that has weather experts buzzing. Typically, Japan’s rainy season lingers into July, but in 2025, it concluded about three weeks earlier than the norm. This marks the earliest end to the rainy season ever recorded in these regions, setting a new benchmark in Japan’s meteorological history.

But that’s not all—the duration of the rainy season was also astonishingly short:

• Northern Kyushu: 19 days
• Shikoku: 19 days
• Chugoku: 18 days

These figures represent the shortest rainy season durations ever recorded in these areas, shattering previous records.

Comparing 2025 to Historical Norms

To put this extraordinary event into perspective, here’s a table comparing the 2025 rainy season durations with historical data:

Region	2025 Duration	Shortest Record	Usual Period
Northern Kyushu	19 days	19 days	June to July
Shikoku	19 days	19 days	June to July
Chugoku	18 days	18 days	June to July

Why Did the Rainy Season End So Early?

According to the JMA, the early end can be traced to a strong high-pressure system dominating western Japan. This system disrupted the usual rainy conditions, cutting the tsuyu period short. Normally, Japan’s rainy season stretches across June and July, but in 2025, it wrapped up in just a few weeks. While the precise reasons are complex, this event underscores the unpredictability of weather patterns—potentially hinting at broader climatic shifts.

Impacts and Growing Concerns

The early end to the rainy season is a double-edged sword. On one hand, residents and visitors in western Japan can enjoy clear skies and drier weather sooner than expected—a welcome relief after days of rain. On the other hand, this shift raises serious concerns:

• Water shortages: Reduced rainfall could strain water supplies, especially in rural and agricultural areas.
• More extreme heat: An extended dry period may lead to a spike in scorching summer days.

Conclusion

The record-breaking early end to Japan’s rainy season in 2025 is more than just a weather anomaly—it’s a historic event that could reshape how we view seasonal patterns in western Japan. From Kyushu to Kinki, this shift brings both opportunities and challenges, particularly around water management and heat preparedness.