Avalanche Road Ask Dave a weather question

Dave Thurlow, Host

 
Hi, I'm Dave Thurlow from the Mount Washington Observatory and this is The Weather Notebook. In the final part of our look at the spring clearing of highway 140 in Yosemite, Robin White reports on the dangerous subalpine commute of snowplow drivers.

"Sometimes the work the Yosemite snowplow drivers do actually creates the danger of avalanches. Dean Glenn manages roads and trails for Yosemite.

DG: 'It's not really a hazard until you make the cut in the road. Once you make the cut in the road, the snow has to go somewhere.'

Avalanche Transceiver

In certain conditions, snow up above the road can slide into the channel created by the snowplow. This means that commuting along the road they have already cleared, snowplow drivers have to pass through avalanche zones on their way to work. In dangerous sections of the road, Yosemite makes drivers use two vehicle teams with only one vehicle at risk at one time. Norm Wilson, Yosemite's avalanche consultant says just in case they get buried in snow, each person carries a beacon.

NW: "This is called a transceiver, it's a transmitter and a receiver. Right now this one is set in the transmit mode. So if I'm buried, my partner will switch to receive and start picking up that signal. ...In the event that someone's buried we could probably start digging for them within about two minutes. That's pretty good."

Pretty good because people trapped in snow can die of suffocation within 4 or 5 minutes. A lesser hazard for the snow clearing team - but one which is more common - is when it starts snowing while they are at work. Sometimes they find themselves having to plow their way... back home again!"

Robin White is an independent producer from San Francisco, CA. The Weather Notebook is underwritten by Subaru the beauty of all wheel drive with major support provided by the National Science Foundation.