They’re open rain or shine, 24 hours, seven days a week.

The Waffle House is open just about all the time, because they say they’re prepared, including for hurricane season.

“We have hurricane meetings, we have pre-hurricane playbooks, we have hurricane handouts we give to customers and associates," said Emily Coleman, a Waffle House division manager. "We have a hurricane check list that we hand out."

So prepared, that FEMA -- the agency that responds to disasters -- uses the "Waffle House Index" to determine how quickly a community can get up and running after a disaster like a hurricane.

If a Waffle House is open and serving a full menu after a hurricane, then they know things are going pretty well and the index is green.

But if the diner is only serving a limited menu, it tells FEMA there may be supply or power issues in an area, that equals a yellow on the index.

A red on the index -- that’s if a Waffle House is closed. Then FEMA knows it’s bad.

FEMA's administrator Craig Fugate started using the Waffle House Index when he was in charge of Florida's emergency response. He says the Waffle House is a good indication of how fast businesses and the community at large can recover after a storm.

Waffle Houses, Home Depots, Walmarts and other businesses have risk management plans in place to open up quickly after being battered by storms. FEMA says a business's quick response time signals a stronger recovery for that area.

“They’re spending a lot of time cleaning up, they’re assessing the damage to their properties, they’re trying to make sure their families are ok, and it’s kind of like a place where everybody can meet," Emily Coleman said. "We tend to be one of the first places to open up.”

After the tornado in Moore, Oklahoma, the Waffle House there had a yellow on the index, but was quickly back to green the following day.

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