Urban avalanche season is here

Heavy wet snow slithered down the gullies above Thane Road Tuesday as a Department of Transportation crew conducted avalanche control.

It was the second time this winter that DOT brought down snow before it could slide.

The road was closed for about two hours. Southeast Maintenance and Operations Manager Greg Patz says the snow stopped just short of Thane Road and no cleanup was necessary.

Urban avalanche danger in Juneau has been high since the rain started to fall on Monday. That has created an upside down snowpack — with high density and wind-driven snow over the looser, lighter stuff that fell over the weekend.

Patz says Tuesday’s controlled slides show more stability than avalanche forecasters expected.

“With all the snow that we’ve gotten, and then with this heavier wetter snow on top of light snow, you’d would expect anything triggering it to cause some big slides and maybe as they come down to pull out more of the deeper snow. And that didn’t happen, so it kind of seems to indicate that maybe there’s a little more stability,” he says. “That’s not to in any way underplay the avalanche danger out there, but we didn’t cause a big movement and big slab avalanches.”

The avalanche crew fires the mortars from a gun mount on a platform at Treadwell on Douglas Island, across Gastineau Channel. Patz says the avalanche crew shot 21 rounds into the main avalanche paths about the road.

“We view it as three main chutes, and there are points that we like to shoot around each main avalanche gully or chute,” he says.

DOT does avalanche control along Thane Road two to three times a year, according to Patz.

Meanwhile, avalanche danger today (Wednesday) in Juneau is moderate to considerable, according to CBJ Emergency Programs Manager Tom Mattice.

In his daily report at juneau.org/avalanche, Mattice says it will be considerable overnight tonight. He expects it to be high again from Thursday through mid-day on Friday. Mattice updates the avalanche warning every day at 7 a.m. and as conditions change.