The move reportedly came because of "unprecedented" snow conditions requiring more aggressive measures to control.

The highway between Cle Elum and North Bend, Wash., was closed for about five hours, while crews worked to clear away the snow brought down from the blasts, said department spokesman Mike Westbay.

More than 6 1/2 feet of snow fell in the area over six days, creating avalanche possibilities in areas that haven't had an issue with the problem in 30 years, the Seattle Times reported Monday.

The helicopter work helped reduce the avalanche risk from moderate to low, added Westbay.