The Valley County (Idaho) Sheriff's Office said in a statement recovery may be delayed "due to weather conditions and a severe storm moving in," the San Jose Mercury-News reported.
The victims were the pilot, Dale Smith of San Jose, his son Daniel, his son's wife Sheree, his daughter Amber and her fiance, Jonathan Norton, the newspaper said.
The family was flying in a Beech Bonanza from Baker City, Ore., to Butte, Mont. when Dale Smith reported engine trouble. Previous searches of the mountainous region had failed to turn up any sign of the plane.
Dale Smith's wife Janis wrote in a post on a website dedicated to the search for the missing family that her husband's brother was among those who located the plane, working from tips from people looking at satellite images of the area on the Internet.
"The snow was very deep and the going was very slow," she wrote. "Less than 2 hours before they needed to wrap up the search for the foreseeable future, [they] found the plane.
"However, we do know my family members on the plane died quickly and painlessly. They did not suffer."
She went on to express the family's gratitude to those who helped find the missing plane.
"There are many, many stories of sacrifice, diligence and generosity throughout this unfortunate event," she said.