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Oracles of powder

National Weather Service

Forecasting powder is an elusive science. But some meteorologists - armed with algorithms, weather models, and a little art - are improving their predictions.

Snow is not created equal, ranging from Utah's dry champagne powder to Sierra's wet cement. And weather forecasting can seem like voodoo. But in the world of powder prophecy, local-centric upstarts like Famous Internet Skiers have the allegiance of some die-hard powder hounds. Tech wizards at San Francisco, Calif.,-based Weather Underground have released a new powder-predicting product. Meanwhile, Weather.com, owned by giant The Weather Channel, and State College, Pa.,-based Accuweather Inc. are focused elsewhere.

"Our computer models don't have enough resolution, and can't provide the specificity people want. Precipitation is difficult to predict. Snow is harder. That's why we give ranges," said Ken Reeves, Director of Forecasting Operations for Accuweather, a top player in the multi-million dollar US forecasting market. "We already had snow types in the 1960s for business clients, but it was pretty subjective. I don't think skiers are looking for that."

Meanwhile, Weather.com, which NBC purchased in 2008 for $3.5 billion, outsources snow forecasting work. "Our ski forecast is part of a partnership with Lebanan, N.H.,-based SnoCountry Mountain Reports," said Melissa Medori, a spokeswoman for The Weather Channel. SnoCountry is a trade association owned by the industry that collects and disseminates current snow conditions as reported from members said Tom Cottrill, President of SnoCountry. Conflict of interest? Cottrill says no, "Ski areas have learned, now they want to meet expectations."

John Celenza, Senior Developer and Meteorologist at Weather Underground said his team's new product, Powder Predictor, works for consumers. "Forecasting comes down to computer models doing straight-up simulations," he said. They input layers of cloud cover and respective temperatures, upward air speed, and temperature of the air from ground to lowest cloud layer. The algorithm produces a colorful map that forecasts fluffiness as the number of snow inches per liquid inch. Thirty is good, forty epic (Imagine melting 40 inches of snow and getting one inch of water).

Celenza snagged a Stanford University Master's degree in computer science to up his forecasting game. "I discovered a whole new world of algorithms -- like machine learning and facial-recognition in cameras -- not being used in weather. So this is what we're going to be using more of. As far as I know, nobody is using the stuff I'm using."

Celenza isn't just a weather geek. "I'm a skier," he said. "If I could go more, I would."

Not everyone agrees with his approach. "Tools like the Powder Predictor work for people a couple hours from a mountain," said Sammy Levine, a New Yorker and former Winter Park, Colo., resident. "I don't care what kind of snow it is. If it's snowing, I'm boarding."

Some won't settle for chance. Chris Nelson, a powder hound who tracks good snow between Vermont and California, is skeptical about Powder Predictor. "Two mountains side-by-side may produce completely different weather patterns which makes it hard to predict. There are just so many factors involved," he said. "I need the most detailed forecast I can find when trying to decide where to go." On the east coast, his go-to is niche forecaster Famous Internet Skiers.

A.J. LaRosa is "the weather man" for Famous Internet Skiers and has 15 years experience. "For all the science involved, it [forecasting] is art. You need gut sense from experience. Mountains are micro-climates; they are like small dots on the map," he said. "To understand where the best snow is falling, you have to understand how the larger weather patterns will interact with specific points."

Those who follow LaRosa are treated to hand-drawn maps and technical jargon which would deter all but the most ardent snow junkies. The payoff is good. "I love winter storms. I feel like a proud parent," he wrote on Sunday. "I saw the potential for this storm, forecasted it, watched it grow and shrink in the models. Watched as this system gathered strength setting the stage for an explosively snowy night."

But despite the storm of predictive science, sometimes, old school still reigns.

"I use long range forecasts such as Farmer's Almanac," said Richard Kang, a skier who makes a big trip west every year. "Since most of my trip are planned at least 1-3 months in advance, it's really up to chance whether it happens to snow. Farmer's Almanac has been surprisingly accurate over the last few seasons."