The woman, who has not yet been identified, jumped from a boat into the frigid water to swim but then became distressed and asked for help, according to officials.
Her husband jumped in with a life vest on to try to help her. Officials said the boat then floated away with the couple’s six children aboard.
“The boat was adrift with six kids on board in middle of Lake by Zephyr Cove,” rescue officials tweeted.
The boat was found around 9 p.m. after people heard the children on board yelling for help, officials told FOX40. The father was later found suffering from “severe hypothermia.”
All were taken to area hospitals for treatment after suffering from varying degrees of hypothermia.
The woman’s body was found just after 9 p.m. Rescuers attempted to resuscitate her but the efforts were unsuccessful and she was pronounced dead.
It’s not yet known why the father could not get back on the boat after jumping into the lake.
The incident remains under investigation.