Get Exclusive App Deals

Koyasan

Koyasan 1
Travel Info
3
Travel Info
Koyasan 2
Koyasan 3
3

Top 10 Must-Do Experiences and Attractions in Koyasan

Reviews of Koyasan activities

Koyasan Weather, Climate and Best Time to Visit

Data source:Meteostat
Update date:2025-09

Koyasan year round climate

  • Spring (March–May): Average 51–65°F, 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 72–83°F, 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 60–80°F, 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 44–49°F, 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. 63.7°F / Annual rainfall: approx. 1794 mm / Summer humidity: 70%–80% / Rainiest month: May

Koyasan monthly average temperature and precipitation

Month
Air temperature (°F)
Precipitation (mm)
January
45°F
63.9
February
45°F
59.2
March
51.1°F
113.6
April
59.7°F
163.5
May
65.5°F
313.2
June
72.7°F
285.1
July
81.3°F
200.3
August
83.7°F
130.6
September
80.6°F
161.5
October
68.9°F
141
November
60.3°F
101.2
December
49.6°F
61.5

Koyasan weather for the next seven days

10/4
Sunday
Overcast
72°F/60°F
10/5
Monday
Fog
67.8°F/59°F
10/6
Tuesday
Sunny
71.6°F/53.3°F
10/7
Wednesday
Sunny
68.4°F/50.7°F
10/8
Thursday
Sunny
73°F/48.5°F
10/9
Friday
Mist
75.5°F/58.9°F
10/10
Saturday
Sunny
76.5°F/57°F