High winds and cool temperatures have turned Memorial Day weekend into an ordeal for boaters on Lake Powell, while snow surprised holiday campers at the Cedar Breaks National Monument, authorities said Monday.

At Lake Powell, boaters became stranded on Castle Rock, just inside the Utah border, National Park officials said.Park officials Sunday evening rescued 22 people stranded on the solid-rock island near Page, Ariz., on the lake's southern-most tip, District Ranger John Benjamin said.

The boaters were forced ashore on the island by high winds and 4-to-6-foot waves on the lake. Park officials removed the people by boat and all were treated for hypothermia, Benjamin said.

Additionally, high winds sunk an unoccupied 45-foot houseboat near Antelope Island on Lake Powell in Utah. Three small boats were also sunk, Benjamin said.

Two of the boats were unoccupied, but divers hope to search one of the boats Monday to determine if it went down with anyone aboard, he said.

"It's a difficult situation," Benjamin said. "It was chaos while the wind was blowing . . . now it's still bad, but it's not disastrous," he said.

Another houseboat overturned in Wahweap Marina Sunday night, and three small crafts were blown ashore, but no one was injured in any of those incidents, Benjamin said.

Several other parties were also stranded in Warm Creek, Utah, on the southern end of Lake Powell, Benjamin said.

"There just a lot of people here totally unprepared for 50 degree weather and high winds," he said.

Several boats were still missing early Monday morning from the Bullfrog Marina, but a ranger there said it was likely that the vessels had found a safe harbor during the storm.

"Most folks down here on the lake are pretty savvy when it comes to high winds," said Bob Martin, Bullfrog sub-district ranger.

Meanwhile, a late-spring snow storm stranded campers at the Cedar Breaks National Monument Sunday, according to Don McAllister, a Utah Highway Patrol dispatcher.

McAllister said the snow also slickened roads in the Cedar City area. Although the National Weather Service said up to 40 cars were stranded earlier Sunday, McAllister said the snow was melting and it "doesn't seem to be too serious right now."

"There are probably a few people who'll have to stay an extra night in their cabins," he said.

The storm also forced the closing of three state roads in central and southeastern Utah Sunday night, the Utah Highway Patrol said.

Only U-95, "the Bicentennial Highway," remained closed Monday morning because of a rock slide. (See related story on B1.)

U-14 was closed Sunday through Cedar Breaks National Monument from Long Valley Junction west to Cedar City because of snowy conditions, the UHP said.

U-191 between Blanding and Monticello was closed Sunday night to high-profile vehicles because of high winds, the UHP said.

Finally, U-666 from Monticello east to Colorado also was closed, the patrol said.

The cold front moved across the state Sunday afternoon, bringing strong winds and moisture.

National Weather Service Meteorologist Ed Carle said wind gusts to 60 mph were reported at the southern Utah town of Milford and gusts to 50 mph were reported in several locations, including the Lake Powell area.

The water temperature at Lake Powell was between 64-65 degrees, according to Tom Davidson, a National Park Service dispatcher at Wahweap, Ariz.