A Look At How Evacuation Zones Are Determined

Sep 2, 2019



With mandatory evacuations ordered up and down the First Coast, people are being asked to check their evacuation zone. But some people don’t have one. 

Map of Duval County's evacuation zones.
Credit City of Jacksonville

Deputy director of emergency management for St. Johns County, Jeffrey Alexander, said that’s because some people aren’t living in areas with a significant wind or water threat. 

“You may you may not be in an evacuation zone,” Alexander said. “That means that based on the hazards of a hurricane, we don't have a hurricane scenario that's going to cause you to evacuate.”

St. Johns County has six areas identified as evacuation zones. They’re cumulative, so if Zone C is asked to evacuate, A and B are automatically included. Those zones are figured out from the National Hurricane Center’s Sea, Lake and Overland Surges from Hurricane (SLOSH) model. 


“(The National Hurricane Center) runs tens of thousands of scenarios of hurricanes affecting this county. They tell us where those different models can bring the water, we take the maximum amount of water that can be in an area, and we use it as a dividing line,” Alexander said. 

So when a hurricane is coming, there’s an analysis of the storm and who may be at hazard of having life-threatening levels of water. He said wind and other miscellaneous dangers are also taken into consideration when dividing up zones. 

While Zones A through E are cumulative, Zone F is a “special zone” based on based on a very specific set of factors and can be added to other zones. 

For instance, St. Johns County Zones A and B, which include the entire city of St. Augustine, the city of St. Augustine Beach and those living in waterfront and flood-prone areas, parts of Zone F — Hastings and Flagler Estates — have also been told to evacuate. 

“The circumstances are there that could cause the same sort of flooding we saw with Irma in those areas, so we want to give them a heads up,” Alexander said.

He also warned against confusing evacuation zones with flood zones. Flood zones are based on flood insurance and can be found on FEMA’s website, while hurricane evacuation zones can be found on county websites. 

Alexander is urging anyone in a mandatory evacuation zone to leave their homes as soon as possible. And for those with no evacuation zone, consider taking in friends in family who may have to evacuate. 

Lindsey Kilbride can be reached at lkilbride@wjct.org, 904-358-6359 or on Twitter at@lindskilbride