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.
Trace parts of your ancestry to a specific group of individuals from 1,000+ years ago. 1  Understand how the migration of our DNA tells the story of your ancestors. 2  Learn the origins of your maternal and paternal* ancestors. 3  Women can only trace their maternal haplogroup.