The weather has never stopped me, at least not yet. It's delayed me. I've ducked under overpasses more than once due to lightning and I've taken longer routes due to flooding. I'd wait out a tornado too... same for tsunamis, volcanoes and earthquakes.
I've talked to people who won't exercise unless it's practically ideal weather. I don't get it. I'd like to be healthy no matter what is going on around me.