There are many indicators emergency management officials use to gauge the level of a disaster.

One lesser-known indicator is whether or not Waffle Houses are open.

FEMA Administrator Craig Fugate first used what he calls the "Waffle House Index" in Florida during an active 2004 hurricane season.

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He noticed that Waffle Houses were among the first businesses to open in the hurricane-ravaged areas of Florida.

There are three stages to Fugate’s Waffle House Index.

“If you go to a disaster area and the Waffle House is closed that’s red. That means it’s really bad,” he said.

Yellow means the restaurant is partially open with a restricted menu – often the case after a power outage. Green means the Waffle House is open and serving a full menu, although Fugate said it’s certainly not an indicator that the community is undamaged.

According to Fox News, only Waffle House locations in mandatory evacuations areas will be closed for Hurricane Matthew. "We're a 24-hour restaurant, so oddly enough shutting down is a big deal for us," Waffle House's Vice President of Culture Pat Warner told Fox News.

WSB Radio contributed to this report.