On most rainy days you can get quite far with checking rain radar prediction. It often doesn't really matter if i cycle somewhere at 16h30 or 17h00, you look at the radar and try to not get wet :'). Most rain is in short bursts, dry periods between, most cycle trips aren't longer than 20-30 mins. And yeah, sometimes you do get wet. That is okay if you got good gear and if it didn't take you by surprise.