Some good tips for rainy weather fun:
Don't step on the manhole covers or anything made out of metal on the streets. They are really slippery.
Don't wear flip-flops. Your feet will end up looking like you belong in the Shire with Frodo.
Avoid wearing light colored clothing. Unless you're into the wet t-shirt contest look.
It's just rain. When was the last time you ran out of the shower screaming with a newspaper over your head?