Man rescued from partially submerged jon boat after more than 24 hours out at sea

A man was rescued from a partially submerged jon boat after more than 24 hours at sea off the coast of Florida, the U.S. Coast Guard said.

The boater -- 25-year-old Charles Gregory -- was last seen departing in the 12-foot jon boat on Thursday night, according to the U.S. Coast Guard Southeast.

The Coast Guard said its Jacksonville watchstanders received a report from his family Friday evening that Gregory had not returned to Lighthouse Park Boat Ramp in St. Augustine, prompting the search.

After searching through the night, an aircrew eventually spotted Gregory Saturday morning "sitting in his partially submerged jon boat" 12 miles offshore of St. Augustine, the U.S. Coast Guard said in a press release.

The Coast Goard released footage of the rescue, which occurred shortly before 10:40 a.m. Saturday, according to a Coast Guard spokesperson. Gregory could be seen sitting in the jon boat as it filled with water, then waving to rescuers.

A Coast Guard Cutter Coho boat crew recovered Gregory from his boat and transferred him to the Station Mayport boat crew.

Once back at shore, he was transported to EMS at Vilano Beach Fishing Pier, the Coast Guard said.

No medical concerns were reported, the Coast Guard said.

"We just want to say thank you so much," his mother, Debra Gregory, told first responders in emotional remarks to ABC Jacksonville affiliate WJXX after her son was taken ashore.

His relieved father said he had initially given up hope as the hours stretched on and called the rescue a "miracle."

"I should never give up hope. Don't give up on the big guy," his father, Raymond Gregory, told WJXX.

Cmdr. Nick Barrow, Coast Guard Sector Jacksonville search and rescue mission coordinator, told WJXX the "odds were starting to be against us" in the search due to Gregory's vessel, which wasn't suited for an offshore environment.

"We are pleased about the outcome in this case and I would like to thank all of our local and state partners who were heavily involved in searching for Charles and bringing him home to his family," Barrow said in a statement.

"While this case resulted in rescuing Charles from a life-threatening situation, it highlights the importance of having safety gear onboard and being prepared for the worst," the statement continued.

Barrow advised anyone going out on the water to bring a life jacket, VHF marine grade radio, signaling devices and an emergency personal locator beacon.

ABC News' Matt Foster contributed to this report.