The temperature range the coat can stand depend from person to person, but it's definitely good down to -4F / -20C (with a thermal top). This is thanks to ClimatShell(TM), the key component of Apricoat insulation. A body temperature recovery technology that manages to increase the temperature around the body by about 30% on average, without adding any weight or volume, without compromising on the moisture and humidity removal and excess heat quickly and efficiently of high-quality of thermal fabric. Thus helping to regulate body temperature and adding comfort in cold conditions, at any level of activity.
In addition, the coat has built-in hood and gloves which help keep you warm.