Climate of Mount Fuji

Temperature

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

Wind

Strong winds are characteristic at Mt. Fuji's peak. The west-northwest or west wind blows throughout the year and the average wind  is 12 meters per second. The maximum  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 1^oC 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  while clouds generated after crossing are called. It is said that they re a sign the weather is about to change.