State Department of Transportation crews will begin work to reopen the North Cascades Highway on March 31.
The road could reopen sometime in May.
Snow depths of 10 feet were recorded this week at the Washington Pass summit — double the amount of snow measured there last year, a transportation department news release said.
Snow below the Liberty Bell avalanche chutes averaged 35 feet deep.
Conditions for clearing the road are similar to those in the spring of 2011, when it took about six weeks to reopen the highway.
The highway closes every year due to avalanche danger. This year, the state closed the section of Highway 20 from Mazama to Newhalem on Dec. 3. It typically reopens between mid-April and early May.