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.
Haplogroup H3 [mtDNA]. Haplogroup H3 is a human mitochondrial DNA (mtDNA) haplogroup descended from Haplogroup H. H3 is the next most common sub-haplogroup after H1 and characterized by the polymorphism T6776C; a basepair in the coding region from locations numbered from 575 to 16,000.aplogroup H3 [mtDNA]. Haplogroup H3 is a human mitochondrial DNA (mtDNA) haplogroup descended from Haplogroup H. H3 is the next most common sub-haplogroup after H1 and characterized by the polymorphism T6776C; a basepair in the coding region from locations numbered from 575 to 16,000.