The Trans-Sierra Ask Dave a weather question

Dave Thurlow, Host

 
If you live where it snows and think digging the snow out of your driveway is tough, consider this. Snowplow drivers in Yosemite National Park have to clear 46 miles of State Highway 140 before the road opens for traffic each summer. Hi, I'm Dave Thurlow for The Weather Notebook and today, Robin White takes a look at the dangers of opening California's highest trans-Sierra road:

Road Conditions Report

"Orville Roan has snowplowed Highway 140 through Yosemite every winter for 26 years and he knows where to look for the dangers:

OR: 'If you get too close sometimes there's an area where the rock melts the snow out and makes a little bear den in there and sometimes it might drop... 25-30 feet.'

What Roan calls a "bear den" is a hole in the snow. Yosemite's granite rock absorbs heat and makes the snow around it melt forming invisible pockets large enough to swallow a snowplow. There are other hazards like the bridges along the way.

OR: 'I generally walk across and look at the bridge first and then look underneath and make sure...that it's still there really. You never know what the weight of the snow is plus the dozer on there cause you're looking at 15 ton plus the weight of the snow on there.'

As if those problems aren't enough there's always the risk of avalanches. Orville Roan is so experienced that he knows exactly where on the road a snow slide is likely to happen. But even with his experience he still checks in with his intuition before going into a dangerous area. He remembers a situation when he was a rookie driver back in 1973.

OR: 'A whole piece broke down but it didn't slide, it just dropped and you just sit there hoping it don't go any further and it didn't... It'll give you gray hair (laughs).'

Join us tomorrow for a ride in a snowplow.

Robin White is an independent producer from San Francisco and frequent contributer to The Weather Notebook. Funding for our show comes from Subaru and the National Science Foundation.