COLD COMFORT

Whether you're going out in snow or rain or at the crack of dawn, there's never been cooler gear to keep you warm. Here, the best way to dress for each condition you'll face.

By Warren Greene

From the None issue of Runner's World

Variable Conditions

When Venting, Go Deep

A long front zipper allows you to control how much heat to keep next to your body. This shirt combines breathability and windproofing with a brushed polyester knit lining, a Gore Windstopper N2S membrane, and a moisture-dispersing knit outer, which means you only have to wear one layer.

The Convertible Option

Convert a jacket to a vest, and back again, with removable sleeves. This jacket features a brushed polyester lining for extra warmth and a water-repellant nylon shell for added protection from wind and water.

Hole in One

Nike's medium-weight sweat-wicking long-sleeve Adventure top has a mesh back that allows excess heat to escape, a deep front zipper and a built-in mesh shelf bra, eliminating the need for another layer. Plus, it comes with extra-long sleeves with thumb hooks, so you can tuck your hands in and out of your sleeves as you warm up and cool down.

Wet Conditions

Ever wonder why you feel colder on a rainy day than on a snowy one, despite the warmer temperatures? "Most people get into trouble when it's in the 40s and raining because they underestimate the cooling rate of rain compared to colder but drier conditions," says Army environmental researcher O'Brien. Water conducts heat more rapidly than air, which means the heat you generate quickly dissipates. Add the cooling effect of wind, and you're in for a miserable experience. The right gear--a shell with a breathable base layer underneath--keeps cold water off your skin while still letting moisture (that is, sweat) to escape.

Shell Appeal

On wet days, look for a shell that will not only keep the rain off your skin, but will vent the moisture you create as you run. Many jackets are made from waterproof, breathable fabrics such as Gore-Tex, and have large vents mid-back and under the arms. Remember, however, that the harder you run, the more you'll heat up, and even the most breathable fabrics may not be able to keep up with your sweat production. So unless it's a downpour, stick with a light shell with a water-resistant coating and good ventilation.