WENATCHEE – A weekend forecast for 1.5 to three feet of snow, high winds and much colder temperatures beginning Friday, Dec. 12, has prompted the state Department of Transportation to close the North Cascades Highway temporarily at midnight Thursday, Dec. 11.
     “Avalanche chutes can fill and release in as few as 20 minutes under the right conditions,” said Twisp maintenance supervisor Don Becker.
     That’s faster than DOT officials can react to keep motorists or crews safe, he said.
     “We don’t want to risk back country recreationists getting caught in a potentially dangerous storm event, either,” Becker said. “We’ll go back in on Monday and evaluate conditions for reopening.”
     Becker said crews will check all parking areas between the two closure gates Thursday night to “make sure everyone is out.”
     While the storm front isn’t expected to bring heavy snow until Friday, “having the gates closed Thursday night will keep anyone who didn’t get the word from getting up there and caught in the weather event that’s coming,” he said.
     Four inches of new snow fell overnight Dec. 9-10.
     “Rainy and Washington passes are 1,000 feet higher than Stevens and 2,000 higher than Snoqualmie, so typically they get more snow sooner and it’s colder,” said Mike Stanford, north central region avalanche technician.
     The key to reopening the highway is stability of snow in the chutes and that will depend on how much snow comes down and the temperature, according to DOT officials.
     “By Monday, we could be looking at avalanche chutes with firm and stable snow or dangerous layers of unstable snow,” said Stanford.
     If the highway can be reopened, it likely would take crews a day or more to clear the roadway for traffic, say DOT officials.
     Highway 20 gates are at milepost 134, seven miles east of Diablo Dam on the west side of 4,855-foot Rainy Pass, and milepost 171, nine miles west of Mazama on the east side of 5,477-foot Washington Pass.
     The North Cascades Highway usually closes between Thanksgiving week and mid December and reopens in late April or early May. The highway closed last winter on Dec. 4 and reopened last spring on May 1.
     More information is available at www.wsdot.wa.gov/traffic/passes/northcascades.