I lived in Palm Beach County the year after Hurricane Wilma. Wilma took out the power through the most populated part of the county. It also destroyed the cable and telephone lines. If your local gas station had gasoline, power, and a computer hook-up, you could buy gas after you waited on line for two or three hours. My boss thought this was hilarious because he quickly learned that if he drove 20 miles north of West Palm Beach City, he could buy all the gas he wanted in Jupiter in northern Palm Beach County.
The overwhelming majority never once listened to the radio to figure out that they could drive for half an hour and buy whatever they wanted. They sat on their hands and waited for someone to fix it for them.
IMO, 35 miles is far enough that it won’t even occur to most of the city people to go there.
The ferals will be quickly ‘consumed’. It is the gangs, who are organizations with many tentacles, to watch out for. They will be coming in squads, and armed well.