2 climbers stranded with hypothermia await rescue off Denali, North America's tallest mountain

Two climbers were waiting to be rescued near the peak of Denali, a colossal mountain that towers over miles of vast tundra in southern Alaska, officials said Wednesday. Originally part of a three-person team that became stranded near the top of the mountain, the climbers put out a distress call more than 30 hours earlier suggesting they were hypothermic and unable to descend on their own, according to the National Park Service.

Weather conditions made attempts to rescue the climbers particularly treacherous this week, the park service said. Cloud cover posed dangers to aviation and ground search crews who were unable to reach the upper part of Denali between 1 a.m. local time on Tuesday, when park rangers received the climbers' initial satellite call, and 9 a.m. on Wednesday, when the National Park Service said rescuers were "waiting for clouds and windy conditions to dissipate on the upper mountain." 

CBS News contacted the National Park Service for updates on the rescue mission Thursday morning but did not receive an immediate response.