User blog comment:Hurricane Layten/Anticipated tornado outbreak now in progress/@comment-31083079-20170207225557/@comment-26074320-20170209114711

I'll explain:
 * FC - new users/retired user rights users
 * EF0 - Patrollers
 * EF1 - Chat moderators
 * EF2 - Rollbacks
 * EF3 - Junior admins
 * EF4 - Admins
 * EF5 - Bureaucrats
 * EF6 - Wiki owner

I hope this helps you :)