Note that two the storms you're referring to (Iselle and Julio) may have similar predicted paths, but they currently 1000 miles away from each other, and will definitely not merge. Iselle is already impacting Hawaii, while Julio will not approach for several days (assuming the current forecast verifies).
Both FTDNA and Ancestry sponsor groups or projects where people in the same haplogroup can exchange information and maybe even find an ancient connection. But Y-DNA and mtDNA are intended to check ancient bloodlines, 10,000-50,000 or so years ago. They are not generally useful by themselves for genealogy.
According to many population geneticists, everyone belongs to a haplogroup or an ancestral clan. This branch of a family tree includes genetic markers that all have inherited from a single ancestor. These markers can be traced back to the groupâs most recent common ancestor.