The agency coined the term “Waffle House Index” during the 2004 hurricane season to measure the effect of a natural disaster on an area. If the eatery shutters or limits menu items during or after a hazard — they know the community took a major hit. The index has three color-coded levels: Green means everything is fine, at least in the Waffle House; yellow is when the restaurant serves a limited menu, meaning the area lost power or they’re running low on supplies; and red is if it’s closed, showing the area has been hit hard. “The Waffle House test...