Authorities say more than 50 people have been taking shifts searching for five missing snowmobilers in northern Wyoming's Bighorn Mountains.

Lt. Mark Conrad with the Sheridan County Sheriff's Office says poor visibility and wintry weather are hindering the search for the group, which was reported missing early Friday by the owner of the Bear Lodge Resort. The snowmobilers were last seen at about 3:30 p.m. Thursday.

The Sheridan Press reported Saturday that Civil Air Patrol planes with infrared capability have been requested to help in the search, but the pilots can't fly in the current weather conditions.

Conrad has said all five of the snowmobilers are from North Dakota and are considered to be experienced. They also are familiar with the Bighorns.