A 17-year-old boy from Massachusetts died in an avalanche in Hell's Canyon near the Snowbasin Ski Area on Sunday, becoming the third person to die in an avalanche in Utah over the weekend.

An avalanche in Idaho on Saturday also claimed the life of a Utahn.

The Weber County Sheriff's Office reported that a Massachusetts man who was skiing with his two sons at Snowbasin became separated from them Sunday afternoon. He later located one son but not the other.

About 5:15 p.m., rescuers found the 17-year-old's body in the path of an avalanche that was about 500 feet long, 75 feet wide and between 10 and 20 feet deep.

The boy's name was not released Sunday night.

Weber County Sheriff's Capt. Klint Anderson said the boy was skiing in an area adjacent to the ski resort that is posted as "not patrolled" by the Snowbasin ski patrol.

"The victim was alone, apparently, when he probably triggered the avalanche" about 2 p.m., Anderson said in a press release. "Though no one saw the avalanche cover the victim, skiers who came after saw the avalanche field, a ski and a helmet."

The victim was found about 6 feet below the surface, Anderson said.

"At that depth, once the snow comes to a stop and compresses, it squeezes the body and will compress the lungs," Anderson said, adding that an autopsy will be performed to determine the exact cause of death.

Anderson stressed that Hell's Canyon is not part of the ski area's managed slopes, which are regularly patrolled and monitored for avalanche threats.

"The victim also did not have a personal avalanche beacon, that would have aided searchers," Anderson said.

The U.S. Forest Service's Utah Avalanche Center said Sunday was the ninth consecutive day with reports of unintentional avalanches in the state. The center lists the current danger of additional avalanches occurring along the Wasatch Front as "considerable."

"Avalanches are probable with human triggers," the center said on its Web site Sunday night. "Avalanche training and experience are essential for safe backcountry travel."

The names of two of the three Utahns who died in separate avalanches while riding snowmobiles Saturday have been released.

Zachary Bryant Holmes, 16, of Farr West, died from traumatic injuries at University Hospital on Saturday night, several hours after he was caught in an avalanche while snowmobiling with friends in the Wasatch-Cache National Forest near Woodland, Wasatch County.

Nicholas Gus Steinmann, 26, of Ogden, died Saturday after an avalanche in eastern Idaho buried him in up to 8 feet of snow and rescue personnel were unable to resuscitate him.

A 44-year-old Richfield man also died Saturday when his attempt to climb the back side of Signal Peak, southeast of Richfield, triggered an avalanche. He was also covered in 8 feet of snow, authorities said. His name was not released Sunday, but the Sevier County Sheriff's Office expected to release his name this morning.