Highway 20 over the North Cascades may not reopen until June, according to a news release from the state Department of Transportation.
The department will start clearing snow April 10 from the 34 miles of highway that close for the winter. That is about a month later than normal.
Though it typically takes four to six weeks to clear the highway, the department is estimating that because of the deep snowpack, it could take eight weeks this year.
Only once in the past 40 years has the highway remained closed through Memorial Day, Department of Transportation Twisp Maintenance Supervisor Don Becker said in the release. That was in 1974, when the road reopened June 14.
Weather, snow slides and many full avalanche chutes have made it unsafe to begin clearing the highway any earlier than April 10.
On a March 16 assessment trip, avalanche and maintenance staff found snow 25 feet deep on the highway under four of the 11 Cutthroat Ridge avalanche chutes.
Under the three main chutes below Liberty Bell Mountain, they found 35 to 45 feet of snow on the highway, and between Washington and Rainy passes they found 15 feet — three times more than recorded in the past decade.
Last year, the Department of Transportation started clearing the highway March 17 and opened the highway April 22.