Mt Fuji is opened to climbers from the 1st of July every year, marking the start of the climbing season.
As the temperature starts to fall from September, amateurs are expected to have a hard time if they try to climb up the mountain after August. In common, starting from 1st July to the end of August is the period for all people to enjoy Mt Fuji climbing.
At the same time of Mt Fuji opening, all mountain huts and mountain buses start operate. Note that amateurs are prohibited from climbing Mt Fuji if there is too much lingering snow on the mountain. As the result, most of the mountain climbers tend to visit Fuji during the summer holiday period.
The most important point of the Mt Fuji in summer is - it is exceptionally cold.
If you dare to climb up the mountain with only an aloha shirt and pants, think again!
Normally, the temperature falls 0.6℃ for every 100m above sea level.
Mt Fuji is marked 3776 metres above sea level, so the temperature of the peak is about 20℃ lower than sea level.
You gonna have your muscles shaken up if you only have your summer clothes ready, as the temperature up on the peak should only be around 10℃.
I have tried this stupidity before. With only short sleeve shirts and short pants, I kept shaking in 5-gome(fifth station). The temperature drops even lower if the weather is not so great. Please be careful!
If you want to enjoy the sunrise of Fuji, of course you will need to climb the mountain at night.
The temperature at night is below 5℃ even if it is in the middle of summer! It is a completely different story from the sea level.
There is an absolute need for every climber to get prepared for the freezing temperature before conquering the mountain.
I once forgot to think about Suntan when I first climbed up Mt.Fuji. So, I got much payoff after that.
The temperature decreases when the altitude increases. However, Ultraviolet increases following the raise of altitude. Ultraviolet do shower onto your skin during daytime, so do bring along with your sunblock.