Mt. Fuji's Nature
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Mt. Fuji's climate : Mt. Fuji's Nature : top
1Mt. Fuji's climate
2Mt. Fuji's geography and geological features
2Mysterious groundwater and springss

Mt. Fuji's climate

Temperature

    Excluding parts of summer, the monthly average temperature at Mt. Fuji's peak is almost always below freezing and the annual average temperature is -7.1oC. Even on days when the temperature at level ground is 30oC, if you climb to Gogoume it drops to 16oC and is only 7oC at the peak. There is a 22oC average difference throughout the year between the level ground of Mishima and Mt. Fuji's peak.

 Monthly average temperature at Mt. Fuji's peak and Mishima

Wind

    Strong winds are characteristic at Mt. Fuji's peak. The west-northwest or west wind blows throughout the year and the annual average wind velocity is 12 meters per second. The maximum instantaneous wind speed at the peak was 91.0 meters (recorded on October 5, 1964) and 84.5 meters at ground level (recorded at Cape Muroto).
    In addition, the average wind velocity in August, the most tranquil month, is 7.4 meters. Considering that you feel a temperature decline of 1oC when the wind speed increases by 1 meter, the strong wind at the peak is extremely severe.

Clouds and weather

    Clouds are formed when warm air and water vapor hit the mountain, making air drift up the incline and the vapor become concentrated. Clouds formed when crossing the mountain are called "kasagumo" while clouds generated after crossing are called "tsurushigumo." It is said that they are a sign the weather is about to change.
Kasagumo
"Kasagumo" just being generated at the peak
    Summer "tsurigumo" and "kasagumo" Winter "tsurigumo" and "kasagumo"
    Summer "tsurushigumo" and "kasagumo"
    		 Winter "tsurushigumo" and "kasagumo"

    {Source: The Nature and Blessings of Mt. Fuji (Shizuoka Prefecture)}