Dauphin island is lovely as s the ride from there to Pensacola. Don't know anything much about Tallahassee. St. Augustine is wonderful if you wanted to detour over to the coast. Of the two I would say that Mobile has better historic/tourist options, is a bit smaller and less commercial and you can find the start of the Underground Railroad Route there (check adventure cycling for maps).

I don't think tornados are much of an issue down on the coast but the winds can be pretty tricky wherever its flat as there is nothing to stop it Hoping that they die down by Sunday so I can ride in the flatlands/prairie to the west of us.

Just my two cents from the west suburbs of Houston.