(CNN) Where there's a will, there's a Waffle House.
Ask anyone who lives in one of the 25 states in the US home to the roadside breakfast mecca, and it's likely they've heard of the Waffle House Index. It's the unofficial measure thought up by a former FEMA official to evaluate how severely a storm hit an area.
The all-day chain has grown into a trusted source for hurricane guidance by government officials and waffle lovers alike--so much so, that concerned residents in Hurricane Dorian's path have consulted with their local restaurant to see how they're planning for the storm.
"Our goal is always to be the last to close, first to open," Waffle House public relations director Pat Warner told CNN.
As of Wednesday afternoon, Waffle House locations in Hurricane Dorian's path in Florida, Georgia and South Carolina will remain open during the storm, Warner said. They're ready to operate with a limited menu, but employees won't be forced to work if officials have ordered mandatory evacuations in the area.
Waffle House is open 24/7, 365 days a year. That's part of its appeal--it's always there, and it's always open--sometimes during a hurricane.
"Seeing a closed Waffle House is shocking to people," Warner said. "They think, 'Oh, this must be pretty bad.'"
Former FEMA administrator Craig Fugate told CNN the Waffle House Index was born out of coincidence, hunger and necessity.
As director of Florida's Division of Emergency Management, Fugate and his coworkers went to assess the damage from Hurricane Charley after it swept across a large swath of the state in 2004. Naturally, they got hungry along the way.
They drove for miles, and the only spot they found open for breakfast was a Waffle House right off the interstate, serving a limited menu. The further south they drove, the more open Waffle House locations they found while other businesses were dark.
"It just happened that if anything was going to be open, it was always a Waffle House," he said.
After three more major hurricanes struck Florida that year and Fugate and his crew made the cross-state trip three more times, they noticed a pattern. So they codified it--and the Waffle House Index was invented.
It's a color-coded key used to evaluate the degree of damage done to an area and what resources they need to recover--all based on whether local Waffle Houses are operating.
Red: Waffle House is closed completely. If Waffle House is closed, that area was probably hardest hit.
Yellow: Waffle House is open, but they're serving a limited menu. This could mean the area is experiencing power outages or water isn't safe to drink, but people can get around.
Green: Waffle House is up and running at peak condition. This doesn't mean everything's perfect in the area, but it's a sign that basic services are intact.
Throughout the next few hurricanes, all during his tenure as FEMA administrator between 2009 and 2017, the key became one of the agency's better indicators of how severely a community had been impacted by a storm, he said.
FEMA told CNN it doesn't base any recommendations for post-storm recovery on the Waffle House Index, but Fugate said consulting with businesses is an important component of clean-up.
"Whether or not they like the Waffle House Index, I know they look at statuses of big-box stores to gauge security impact, the ability of those stores to get online and take some pressure off the government response," he said.
To determine whether shops should fire up the waffle irons or not is tricky. Dorian's constant changes have made it difficult to pin down a quick solution, and closures and reopenings could come more quickly than the time it takes to fry an egg.
Just two days ago, Warner said about 300 locations were in the storm's path, and 99 of them were susceptible to damage. But Dorian's been downgraded to a Category 2, so they'll stay open unless things get dangerous.
They're preparing as best they can, Warner said: They've stocked restaurants in affected areas with extra food and supplies before the storm, and they're working with in-state food vendors for post-storm supply.
They've also staged generators outside of buildings in case they lose power, and stores in other areas are ready to step in to help if needed.
And yes, they talk to FEMA, as well as state and county officials.
"The planning gets us up to the storm," he said. "Then, it's all about reacting."
Several Waffle House locations might see some rain, others some power outages, but they'll all keep cookin' as long as they can throughout Dorian's trip up the Atlantic coast, even on a scaled-down menu.
Warner did give one note of caution: He described the idea that local Waffle Houses are frying hash browns while towns are underwater and out of power as an "urban myth."
"You do not want to ride out a storm in a Waffle House," he clarified.
If things do shut down, staff aim to reopen as quickly as possible after the storm passes, he said.
For instance, when Hurricane Michael, a Category 5 storm that hit the Florida Panhandle last October, sent a billboard hurtling through the roof of a Panama City Waffle House, the restaurant deployed its food truck to feed the masses.
People needed to eat.
"This is not a money-maker for us," he said. "But from the people standpoint, it's the right way to do it."
There's something comforting about the warm glow of the tall yellow sign that light up highways, he said--Waffle House means normalcy.
"It shows people, 'Ok, we made it through,'" he said. "Yes, the storm was terrible, but we're getting back to normal."