Spring snowstorms, sudden warming pose dangers

With unpredictable spring weather in Utah, a warm sun one day or a storm that brings snow to higher elevations the next day both can mean one thing — an increase in avalanche danger.

Deseret Morning News graphicAvalanches: Why they occurRequires Adobe Acrobat.

"It has been overall a safe winter," said Drew Hardesty, avalanche forecaster for the Utah Avalanche Center.

Last avalanche season, however, there were a record-setting eight fatalities — people who died as an unexpected wall of snow cemented them into temporary graves.

This season there have been two avalanche-related deaths.

Marshall Higgins became trapped on New Year's Eve while snowshoeing the Primrose Cirque area at Mount Timpanogos. Higgins is still buried under snow due to dangerous recovery conditions.

Earlier this month, the body of snowboarder Ryan Smedley, 34, was found in Taylor's Canyon near Ogden's Snowbasin Ski Resort.

Now that it is spring, predicting avalanche dangers depends entirely on watching weather patterns, according to Hardesty. If there's no change in the weather, chances are the danger level stays low.

"Right now it sort of spikes like an EKG monitor," Hardesty said of Utah's recent weather and related avalanche danger.

A new storm was expected to blanket the entire state beginning last night and lasting through today, according to Chris Gibson, meteorologist with the National Weather Service in Salt Lake City.

Snow is expected above 5,000 feet, with rain hitting the valleys. Gibson's office issued a heavy snow warning for central and southwestern Utah, predicting 12 inches in 12 hours or at least 18 inches of snow within 24 hours in higher mountain areas.

Utah can expect a break with dry, springlike conditions starting Wednesday afternoon and continuing into Saturday night, according to Gibson.

With a warm spring sun, Hardesty said, surface snow on sun-exposed slopes melts and percolates underneath, increasing the chance for what he calls a wet avalanche as the base beneath erodes away and weakens.

But there also have been times recently when a heavy amount of snowfall has come within a short period. What can happen then is a density break in the new snow that causes a slide, according to Hardesty.

Fatalities occur, he added, when people do not consult his office's advisories. Call 801-364-1581 or visit the following Web site: www.avalanche.org/~uac.

Those who are new to checking an advisory should be prepared to know words and terms such as crust, bed surface, slab and brief ridging. Advisories also come with a weather report.

So, check the weather and avalanche forecast on a daily basis and practice the "usual combat techniques" if you're in the backcountry. Hardesty said that means skiing with a partner. Each skier should carry an avalanche transceiver (about $100 on e-Bay, according to Hardesty), probe pole and shovel.

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E-mail: sspeckman@desnews.com