Hurricane Ian has strengthened, with winds now at 85 mph, as it continues to move northward off the east coast of Florida.

The forecast track has shifted a little farther north with the latest advisory at 11 p.m. ET, putting cities like Myrtle Beach, S.C., in the storm's path for worse impacts, while less impact could be seen in Charleston.

Wind Gusts up to 90 mph are possible in Myrtle Beach on Friday afternoon, as Ian is expected to make landfall toward the south. Much of Georgia to the Carolinas will experience wind gusts over 50 mph.

-ABC News' Riley Winch

Despite water receding in Fort Myers following Hurricane Ian's destructive path across Florida, 80% of the city is still without power, while 70% is without water, Mayor Kevin Anderson told ABC News Live Prime.

Anderson said the most important thing is to get electricity and water back up and running for residents, especially since it's still hot and humid in the area and people need air conditioning and water.

"Tomorrow, we're expecting the delivery of the pods with the water and food and ice and we'll be setting up delivery stations," he said. "Again, the problem is it's very, very difficult to live here without air conditioning."

Fort Myers has performed about 200 rescues and counting, according to the mayor.

"The crews were out and they're probably still out there working now, getting the roads cleared and getting the roads where they're traversable so that emergency vehicles can respond," Anderson said.

Eva Neocleous, her mother, Aurora, and dog, Primi, waited more than 24 hours to get rescued from their Fort Myers home in the aftermath of Hurricane Ian.

The family first called for help at 11 a.m. on Wednesday, but conditions were too dangerous for first responders at the time. Nobody came until the Cajun Navy pulled them out around 12:30 p.m. Thursday.

Neocleous said the ordeal was terrifying: "I thought I was going to die right there."

-ABC News' Rachel DeLima, Andrew Fies and Victor Oquendo

There have been more than 700 confirmed rescues in the aftermath of Hurricane Ian slamming Florida, Gov. Ron DeSantis said Thursday.

The Sanibel Causeway, which suffered significant damage in the storm, will most likely need to be rebuilt entirely, he said.

There were more than 2.3 million customers without power in the state just before 9 p.m. ET Thursday.

-ABC News' Darren Reynolds

Tropical Storm Ian is marching toward the Gulf Coast of the U.S., a region quite vulnerable to hurricanes.

The underwater geology of the Gulf of Mexico is what makes the Gulf Coast particularly unguarded to the massive influx of seawater, said Michael Brennan, acting deputy director of the National Hurricane Center, according to an article on Inside Science.

The symmetry of the Gulf of Mexico, with its shallow, sloping continental shelf, allows the storm surge to be pushed even higher onto land, Brennan told the outlet.

Because the land around the Gulf Coasts is typically flat, that exacerbates the flooding even more and allows the storm surge to travel farther inland, Brennan said.

"Of all of the hazards of hurricanes --- winds, rain, storm surges –-- surges are what can cause the largest loss of life," Brennan told Inside Science.

The Tampa Bay-St. Petersburg area, one of the regions bracing for Ian, is especially vulnerable to storm surge flooding but has avoided a direct hit from a strong hurricane since 1921.

Editor's Note: This post has been updated to reflect proper attribution to Inside Science.

-ABC News' Max Golembo