Having grown up in a very dry part of the US, I think of water falling right down out of the sky is a bit weird, but I deal and ride in it anyway.
Anything from a mist to a good heavy drizzle can be enjoyable, as the rain clears the bike paths nicely, and isn't overly uncomfortable. Anything more is just no fun - but I've done it and lived to tell about it.
Actually, come to think about it, I'd rather ride in a cool rain than heat and high humidity.
My cateye Astrale 8 seems to be waterproof, but it is hidden behind my fairing, which keeps a good deal of the rain off.
Give big space to the festive dog that make sport in the roadway. Avoid entanglement with your wheel spoke.
(Sign in Japan)
1978 Raleigh Gran Prix
2003 EZ Sport AX