Best Time to Visit Japan for Outdoor Exploration?

Hi everyone,

I'm planning my first trip to Japan and could use some advice. I've been thinking about visiting in August, but I've read mixed things about the weather. Is it generally too warm to enjoy outdoor activities, or is it manageable? I really want to spend most of my time exploring and not be limited to indoor activities because of the heat or bad weather.

For those of you who have been to Japan, what month do you think is the best for exploring all day and seeing multiple attractions? Ideally, I'd like to do 2-3 things each day without worrying too much about the weather.

I would like to avoid peak/high season. So what are my options?

Thanks in advance for your insights!