Snowflakes are tiny ice crystals. So how can something made of ice be so sticky?
“Boy, that makes it miserable when snow builds up on the skis,” said Lee Metzger, a longtime cross-country ski advocate and retired University of Montana wildlife biology professor. “Everybody thinks because they have waxless skis, they don’t need to wax them.”
While the past several days have delivered lots of fresh snow to the Rattlesnake, Pattee Canyon and Blue Mountain trails around Missoula, they’ve also come with daily temperatures hovering around the freezing point. That provides perfect conditions for packing snowballs and snowmen. But it leaves skiers jerking and sliding like Frankenstein at the disco.
“The reasons get complicated pretty quickly,” National Weather Service meteorologist Trent Smith explained. “When you’re skiing, you’re causing friction and creating water from ice. Water has a very strong bond to itself, so it sticks to things. That’s why it’s sticky snow.”
Temperature also determines the crystal formation of snow, which further affects ski performance. Around 32 degrees, snowflakes form in the classic Christmas-card star shapes technically called dendrites or plates. When the air is warm, those flakes stick to each other, resulting in the really big puffs of falling snow.
Colder temperatures between 25 and 15 degrees produce snowflakes in needle, column or prism shapes that don’t connect together as well. Paradoxically, between 15 and minus 7 Fahrenheit we get a return of the plates and dendrites, but in larger sizes. That’s what ski areas refer to as “champagne powder.”
Contemporary cross-country skis usually work great in those temperatures. But if you’re determined to head out around the melting point, there are tricks you can use to get around.
“On days when the snow is super wet and heavy, when it sticks and clumps to bottom of your ski, you want some glide wax,” said Meg Wicher of Missoula’s Parks and Recreation Department. “It comes in little metal tins. Make sure you’re applying to every part of ski that touches snow, and work from tip to tail.”
Wicher said some skiers still like to heat their skis with an iron before applying hard wax. That kind needs to be buffed with a piece of cork or special plastic to maintain a smooth surface. But it arguably lasts longer than the softer, wipe-on materials.
Metzger uses that method, but also keeps a plastic bag with the softer glide wax in his kit for touch-ups.
“I also have a can of spray silicone for the textured bottoms of my skis,” Metzger said. “It keeps stuff from building up and helps a great deal. I’ll turn the skis over and spray the bindings, which keeps the snow from building up on the binding and underfoot. I’ll spray my ski boots, too, for the same reason.”
Metzger said he uses a waterproofing silicone spray such as would be used to maintain a rain jacket for his winter gear. He has used the techniques in all temperatures in his 10 to 20 cross-country outings a winter. But he doesn’t worry about the multiple wax formulations developed for waxed skis in different conditions.
“It’s been decades since I used waxed skis,” Metzger said. “For people who really like that and really want to squeeze glide performance out of their skis – have at it. The textured bottoms of waxless skis are so high-performance now, that unless someone has a compelling reason, I say don’t even look at them.”