When it’s too cold for gloves — generally around 10 degrees Fahrenheit for me — a good pair of mittens is crucial to enjoying any 
wintertime adventure. You sacrifice dexterity for cozy digits, but that’s the price of warmth in the rock-bottom cold months of the year.
So what mittens are the best for outdoor enthusiasts who want to ski, climb and throw snowballs at friends? A few years back, I tested six pair of top-end mittens for three months to find out.
Granite Gear’s Lutsen Mitts (orig. $89 but now discontinued; http://www.granitegear.com), a stout waterproof-breathable pair with wool fleece liners, nudged out first place in my little competition. The company stopped producing mittens. But, with my pair, the simple, streamlined construction and a non-bulky liner let me clip a carabiner and tie knots when ice climbing. They fit well and had a durable leather palm. Also, they were among the warmest in the review, holding their own in temps down to 20 degrees below zero. So if you can somehow still find a pair, buy ‘em.
A close second place goes to Black Diamond’s Mercury Mitt ($86, http://www.blackdiamondequipment.com). The company described them as cocoons for the hands, and indeed they’re stuffed with 284 grams of Primaloft insulation, the same fill used in cold-weather sleeping bags. They are nice waterproof-breathable mitts, but dexterity was not as good as with Granite Gear’s discontinued Lutsen Mitts. With the newest rendition of the Mercury Mitts, Black Diamond added a “trigger finger” removable liner that separates your index finger from the rest, increasing dexterity.
Marmot’s Expedition mitts ($110, http://www.marmot.com) take the warmest-of-all award. Made for Mount Everest climbers and South Pole scientists, the puffy Primaloft-stuffed waterproof mitts kept my hands toasty in extreme temps (as low as minus 30). In fact, the Primaloft is said to be twice as warm for its thickness than any other insulation. But the abundant insulation creates a mitt that lacks dexterity — I could easily grip a ski pole, but anything more than that was difficult.
The Cloudveil Troller mitts ($80, http://www.cloudveil.com), a classic leather mitt with a soft-shell back for stretch and breathability, is a nice model that deserves an honorable mention. It’s a neat combination, and the mitt balances warmth and dexterity well. Wear them on cold days down to 10 degrees or below.
—Stephen Regenold
Roanoke Outside Blog 