Unlike, say, sleeping bags, there's no accurate temperature rating system for shoes. How a shoe handles the cold (or, rather, how a person handles the cold in a shoe) depends on factors beyond air temperature, including: ground temperature, humidity, blood circulation in your feet, foot mobility (the more you move, the warmer you might feel) and, of course, the socks you're wearing (or not wearing, as the case may be).
The short answer is, the Alpine has 200g insulation, rated to -32°C/-25°F.
With the seam sealed bootie, heat-reflecting insole, insulated synthetic lining, and lugged sole, we're giving you a cozy natural movement option for staying warm in the cold.