Hurricane Erin raced from a Category 1 to a Category 5 storm. If Erin keeps ramping up, is there a Category 6?

As of Saturday morning, Air Force Reserve Hurricane Hunter aircraft indicated that Erin has become a Category 5 hurricane.

Hurricane Erin, now a Category 5 storm, with maximum sustained winds of 160-mph, is expected to continue strengthening.

Hurricane Erin is now a Category 5 storm, the highest on the class, rapidly intensifying overnight into early Saturday ...

Spaghetti models predict Erin will skirt the U.S. East Coast by hundreds of miles as it moves north through next week.