The woman's husband was found about two hours earlier, at 2 a.m. after he ran the boat aground. He told police that he didn't know his wife was missing and that he thought she was sleeping below deck, the AP reported. He said the last he had seen his wife was earlier in the afternoon, the Journal reported.
The incident is under investigation.
"The story's a little cloudy," Coast Guard Petty Officer Sam Van Lent told the Journal.