The rough seas off the Azores Islands on Thursday killed one person, a young girl, while 12 others survived.
Four yachts called in to shore for help because of the severe storm, the Associated Press reported.
One of the boats was carrying a French couple and their two children, officials said.
The sailboat sank and the 6-year-old girl, who had spent hours in the ocean while they were waiting to be rescued, died later of hypothermia, according to the AP.
The mother and 9-year-old son were picked up by a merchant ship after managing to climb onto the yacht's lifeboat.
The aircrafts involved in the rescue came from both the Portuguese air force and the US Coast Guard. They were training together as part of a joint naval exercise when the emergency calls came in.
The Portuguese authorities released a video of parts of the rescue today, showing responders dropping down and bringing the stranded vacationers up to the helicopter.