I would say a mountain bike with tubeless tires or slime tubes is going to be most beneficial. Second thought would be a cross bike again with slime or super tough tires. Lights or at least little blinkies, even in daylight this draws attention with chaos it is helpful. So sorry for your daughter to lose a friend, at least she has her sorority family to help her and vice versa.

We don't have basements in Texas but do know the proper drill, we practiced it often in school. My husband and I have had to cram into our guest bath tub (most interior part of house) with our cat and dog. No matter how often you've done it you never get used to it. A tornado hit the next town (F1 scale) but it sounded like it was closer than 12 miles with that storm.