We get a fair amount of severe weather and lighting. A lot of people get struck by lightning every year around here so there is quite a bit of coverage in the media and they try to increase peoples awareness of the dangers.
If the weather report says a possibility of lightning I'll usually ride, and keep my and eyes and ears open for confirmation. If the weather reports say definite thunderstorms I usually wont go out in it.
I commute on a steel bike and a lot of my route is fairly wide open and exposed, so if I do get caught out, I'll find a place to stop take shelter if only until it passes which usually isn't too long. These kind of surprise storms are generally pretty fast moving around here.
And no, your rubber tires will do nothing to insulate you from a lighting strike.