The 35-mile stretch of highway has been closed since Saturday evening, after trees crashed down on two cars and killed two people.
DOT officials say dozens of snow-laden trees slumped over the roadway since Saturday shed the excess snow on their branches, straightened, and are no longer threatening to fall onto the highway.
Warmer than forecast temperatures and a steady breeze Monday night caused most of the snow and ice on tree branches to release. By Christmas morning, no more trees had fallen. With continued warmer temperatures, a breeze and much lighter than expected snowfall, by mid-Tuesday afternoon, DOT maintenance crews determined the threat of falling trees had diminished to the point that the highway could reopen.
The highway is one of two primary east-west routes through the mountains usually open during the winter.
On Friday, a large tree came down on an SUV with a family of six inside, killing a Bothell couple and injuring their four children. Then, on Saturday, a car with five people inside slammed into a fallen tree, injuring everyone inside the vehicle.
The DOT's maintenance supervisor for Stevens Pass has been working in that area for 30 years and had never seen conditions like it.