Want to know how bad hurricane damage was after it hits? Check out which Waffle House restaurants are open.

“Waffle House became almost like a rough guidepost,” former FEMA director Craig Fugate, the creator of the index, told FOX Business. “If it was open and had a full menu we probably weren’t in the worst-hit areas yet.”

“Those restaurants were marked green,” Fox wrote. “A restaurant that was open with a limited menu – probably wasn’t in the hardest-hit area – and was tagged yellow. Any restaurant that was closed was red.”

The guidepost is now known as “The Waffle House Index,” and began after Hurricane Charley hit in 2004.

TRENDING: BREAKING REPORT: President Trump to Nominate Amy Coney Barrett to Replace Ginsburg on the Supreme Court

“The measure is based on the reputation of the restaurant chain Waffle House for staying open during extreme weather and for reopening quickly, albeit sometimes with a limited menu, after very severe weather events such as tornadoes or hurricanes,” according to Wikipedia.

Waffle House, it turns out, has 340 restaurants in Florida, all open 24 hours a day. Tracking which are open and which are closed shows how severe the hurricane damage is.

Waffle House execs held their own meeting on Friday, the New York Post reported.

“We take let the state and county take the lead,” public relations director Pat Warner said. “Right now we’re watching the storm, waiting it out and getting teams ready for what they might need to.”

“Right now we’ve activated our storm center so we are mainly tracking the storm and positioning some resources, but still it’s kind of early because I don’t think anyone has a good grasp on where the storm is going to go,” Warner told Fox.