FRISCO, Colo. (CBS4) – Avalanche forecasters across the state are working overtime, dealing with waves of heavy snow causing major slides in places they are typically not seen. One of those slides came down in dramatic fashion near Copper Mountain on Sunday.

(credit: CBS)

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The avalanche was captured on video from drivers caught in the thick of it. Avalanche forecasters with the Colorado Avalanche Information Center (CAIC) were watching the area closely.

(credit: CBS)

“It’s an unusual event. We understood what was happening, but we didn’t understand the magnitude,” Ethan Greene, CAIC Director, said.

CAIC has few options in the stretch of Tenmile Canyon where the slide happened. Mitigation requires helicopters. Since a slide had not reached lanes of the interstate in decades, they made the decision to leave the highway open.

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(credit: CBS)

“The last time an avalanche impacted the interstate in that area was a 1983. Although we monitor that area, we’re well aware of it most of the slides it don’t post a threat to the interstate,” Greene explained.

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Mitigating in Tenmile canyon is rare. Crews use a helicopter to launch turkey-sized bombs from high above to bring down the snow. An operation like that could leave the vital passage through the mountains closed for hours.

(credit: CBS)

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Forecasters are continuing to monitor the area and plan more mitigation for other highway mountain passes Wednesday morning.