Our tour group of seven didn't feel like we were being herded. Although we only visited three attractions, the leisurely pace was a great experience. It was a pity we didn't see the autumn leaves at the right time! Our guide and driver, Mr. Xu, was very polite and occasionally introduced the features of the attractions, fulfilling his responsibilities admirably. Thumbs up!
Anonymous User
Friend
Koyasan Weather and climate
Data source:Meteostat Update date:2025-09
Koyasan year round climate
Spring (March–May): Average 10.6–18.6°C, mild and comfortable climate, but with relatively high rainfall, especially in May. Common activities: Visiting Koyasan temples, hiking (be aware of changing weather conditions). Recommended clothing: Light jacket, long-sleeved shirt, rain gear.
Summer (June–August): Average 22.6–28.7°C, hot and humid, with occasional showers. Common activities: Visiting temples, experiencing local culture, escaping the heat in the mountains. Recommended clothing: Breathable and sweat-wicking clothing, sun hat, rain gear.
Autumn (September–November): Average 15.7–27.0°C, comfortable and pleasant climate, with reduced rainfall. Common activities: Autumn leaves viewing (in some areas), visiting temples, hiking. Recommended clothing: Light jacket, long-sleeved shirt.
Winter (December–February): Average 7.2–9.8°C, cold and dry, with little rain. Common activities: Visiting temples, experiencing onsen (in nearby areas). Recommended clothing: Warm jacket, sweater, scarf, gloves.
Koyasan climatological average
Annual average temperature: approx. 17.6°C / Annual rainfall: approx. 1794 mm / Summer humidity: 70%–80% / Rainiest month: May
Koyasan monthly average temperature and precipitation
Month
Air temperature (°C)
Precipitation (mm)
January
7.2°C
63.9
February
7.2°C
59.2
March
10.6°C
113.6
April
15.4°C
163.5
May
18.6°C
313.2
June
22.6°C
285.1
July
27.4°C
200.3
August
28.7°C
130.6
September
27°C
161.5
October
20.5°C
141
November
15.7°C
101.2
December
9.8°C
61.5
Koyasan weather for the next seven days
11/16
Sunday
Sunny
17.9°C/5.7°C
11/17
Monday
Patchy rain nearby
16.7°C/6.7°C
11/18
Tuesday
Patchy rain nearby
10°C/3.9°C
11/19
Wednesday
Patchy rain nearby
10.9°C/2.7°C
11/20
Thursday
Patchy rain nearby
11.7°C/5.6°C
11/21
Friday
Partly Cloudy
13.5°C/4.7°C
11/22
Saturday
Sunny
14.4°C/4.8°C
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