The leaders in the Iditarod Trail Sled Dog Race were less than 200 miles from the finish line Wednesday after a night of stormy weather and bitter cold.

The trek was in its 12th day, and race officials said they expected the winner to cross the finish line late Wednesday or early Thursday.Joe Runyan, winner of the 1989 Iditarod, arrived at Koyuk's City Hall checkpoint, 992 miles from the starting line in Anchorage, at 1:56 a.m.

Defending champion Susan Butcher arrived at 3:03 a.m. and Rick Swenson was close behind at 3:19 a.m. They have each won the 1,163-mile, Anchorage-to-Nome race four times.

The leaders were still in Koyuk several hours later as they tended to their dogs and equipment.

Wind gusting to 60 mph drove wind-chill temperatures down to 100 below zero overnight, forcing a couple of racers to return to Shaktoolik, Iditarod officials said.

Butcher and another half-dozen teams were forced to seek shelter in a cabin for a time between Shaktoolik and Koyuk.

The segment from Shaktoolik to Koyuk is one of the most dangerous on the trail, because it includes about 40 miles of Bering Sea ice where there's little protection from wind and cold.

Extreme cold and heavy snow slowed the pace Tuesday and 40 mph wind caused a virtual whiteout.