Planning for the weather is a good way to make your trip to Fujikawaguchiko relaxing and enjoyable, especially when you're splurging. The hottest months are usually August and July, with an average temperature of 20°C, while the coldest months are January and February, with an average of 2°C. The rainiest months in Fujikawaguchiko are July, September, October and June, with each month seeing an average of 290 mm of rainfall.