I live in a rural area on the northern plains. One of the reasons I moved here was because the people were so friendly when I biked across the US years ago. The only hesitation I would have about approaching a farm house and asking for shelter during a thunderstorm would be in wondering where the dogs were (oops, let's not get sidetracked on dogs).

Besides the lightning, with a bad thunderstorm you also have to worry about getting hit by a car due to the poor visibility. Plus, there are often high straight line winds -- we get 70+ mph winds every spring with thunderstorms. Time to head for the ditch or other shelter with those.

Ok, I wasn't on a bike, but I once got caught in a thunderstorm in Montana. I was on an open mountainside while on horseback, herding sheep, when lightning struck less than 100 yards from me -- you've never seen a guy get off a horse faster than I did at that point. I led the horse to a low spot and hunkered down while we experienced thundersnow and lightning stuck about a dozen times right around us over the next 15 or 20 minutes. It was scary! If you can keep riding your bike in those conditions, you're a lot tougher than I am. If I see anything like that on my bike, I'm bailing off.