Charleston International could reopen early Sunday rather than Saturday as originally announced.
One reason for the delay is that the wind forecast began to turn unfavorable after the first estimate was released Friday afternoon, airport CEO Paul Campbell said.
Also, he said, critical Air Force personnel who evacuated this week because of the storm threat must return before commercial flights can resume.
In addition, the evacuation order for the area has not yet been lifted.
The Air Force said it's "possible the runway will be operational" at 6 a.m. Sunday assuming the weather cooperates.
“We are committed to not only protecting the base from the effects of the storm but also assessing and recovering from any damage in a timely fashion,” said Col. Clint ZumBrunnen, 437th Airlift Wing commander.
The runways and airport were shut down late Wednesday in response to Florence, which was downgraded to a tropical storm on Friday after making landfall in Wilmington, N.C.
The closings have led to roughly 320 canceled arrivals and departures at Charleston International through Friday. Another 80 flights have been grounded for Saturday.
Passengers are being advised to check with their airline for information on cancellations, for rebooking assistance and for information on travel waivers.