Japan rainy season — known as tsuyu (梅雨) — brings weeks of grey skies, high humidity, and frequent rainfall. For 2026, tsuyu has already started in Okinawa (around May 4) and Amami (around May 3), both earlier than average. The rest of Japan is expected to follow from late May through mid-June.
This page is updated as the Japan Meteorological Agency (JMA) announces new regional forecasts. Last updated: May 28, 2026.
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What Is Tsuyu? Japan's Rainy Season Explained
Japan rainy season — called tsuyu (梅雨) — is a seasonal weather pattern caused by the collision of cold air from the north and warm, moist air from the south. It typically lasts 4–6 weeks per region, making it one of the most impactful seasons for daily life in Japan. While Hokkaido does not have an officially designated rainy season, the rest of Japan experiences significant rainfall, increased mould risk, and heavy humidity during this period.
Japan Rainy Season 2026: Onset Forecast by Region
| Area | 2026 | 2025 |
|---|---|---|
|
Okinawa |
May 4th |
May 5th |
|
Amami |
May 3rd |
May 5th |
|
Southern Kyushu |
TBA |
May 16th |
|
Northern Kyushu |
TBA |
May 16th |
|
Shikoku |
TBA |
May 17th |
|
Chugoku |
TBA |
May 16th |
|
Kinki |
TBA |
May 17th |
|
Tokai |
TBA |
May 17th |
|
Kanto-Koshin |
TBA |
May 22nd |
|
Hokuriku |
TBA |
May 22nd |
|
Southern Tohoku |
TBA |
June 23rd |
|
Northern Tohoku |
TBA |
June 23rd |
#2: The End Of The Rainy Season
| Area | 2026 | 2025 |
|---|---|---|
|
Okinawa |
TBA |
June 7th |
|
Amami |
TBA |
June 9th |
|
Southern Kyushu |
TBA |
June 27th |
|
Northern Kyushu |
TBA |
June 27th |
|
Shikoku |
TBA |
June 27th |
|
Chugoku |
TBA |
June 27th |
|
Kinki |
TBA |
June 27th |
|
Tokai |
TBA |
July 27th |
|
Kanto-Koshin |
TBA |
July 28th |
|
Hokuriku |
TBA |
July 29th |
|
Southern Tohoku |
TBA |
July 18th |
|
Northern Tohoku |
TBA |
July 18th |
How to Survive Japan Rainy Season as a Foreign Resident
With Japan rainy season 2026 already showing an early start in southern Japan, now is the time to prepare. Here are the essentials for foreigners living in Japan:
1. Choose a Sun-Rain Dual-Use Umbrella (晴雨兼用)
Japan rainy season is no longer just about steady drizzle. Modern tsuyu is increasingly defined by guerrilla rainstorms (ゲリラ豪雨) — sudden, intense downpours that are highly localised and can catch even weather forecasts off guard. But on dry days, temperatures can climb close to 40°C. This is why a 晴雨兼用 (sun and rain dual-use) umbrella is the smart choice: it works as both a rain umbrella and a UV-blocking parasol. It may surprise you, but carrying a parasol is no longer just for women in Japan — men increasingly use them too, and for good reason.
2. Fight the Humidity at Home
Humidity during Japan rainy season regularly exceeds 80%. Without a dehumidifier or regular ventilation, mould can develop on walls, clothes, and food within days. Running your air conditioner on “dry mode” (除湿) is also effective.
3. Wash Clothes Strategically During Tsuyu
Clothes take much longer to dry during Japan rainy season. A tumble dryer or indoor drying rack with a dehumidifier nearby makes a big difference. Many Japanese homes use drying fans designed for indoor laundry.
4. Take a Tip from Japanese Bento Culture
In Japan, it is common to place an umeboshi (梅干し, pickled plum) in a bento lunchbox during the rainy season. This is not just tradition — umeboshi has natural antibacterial properties that help prevent food from spoiling in the heat and humidity. It is a simple, time-tested habit worth adopting at home too, especially when storing rice-based meals.
👉 For a full preparation checklist and recommended products, see our guide: Japan Rainy Season: When and How to Prepare
Frequently Asked Questions
When does rainy season start in Tokyo in 2026?
The JMA has not yet confirmed the start date for the Kanto-Koshin region (which includes Tokyo). Based on the historical average, tsuyu in Tokyo typically begins around June 7. In 2025 it started on May 22 — significantly earlier than average. This page will be updated as soon as JMA makes an announcement.
Does it rain every day during tsuyu?
Not necessarily. Tsuyu brings a higher overall chance of rain and overcast skies, but sunny days do occur. The most intense rainfall usually comes in concentrated bursts, especially in late June and early July.
Is 2026 rainy season starting early?
Yes — Okinawa and Amami entered the rainy season 6–9 days earlier than average. Whether this trend continues for the rest of Japan remains to be seen, but an early start in the south often signals an earlier-than-average season nationwide.
Does Hokkaido have a rainy season?
No. Hokkaido is the only major island in Japan that does not have an officially designated rainy season. It tends to be cooler and drier during June and July compared to the rest of Japan.
