Not too hot and not too cold. Its the nice refreshing mornings and evenings where I can go outside and sit on a bench and enjoy the crisp air and colorful leaves falling.
Best outdoor season. Early spring is similar. No bugs, crisp and cool so you can be active and not sweat too much, and you don't have to slog through snow. After that, winter.
We don't have real seasons in tropical countries, so I'll say rainy season.
it's always a little cloudy, rainy and cool...my favorite weather :)