Hoody Coefficient Storm. For breathable warmth and wind resistance on cold days in the alpine, the Coefficient Storm Hoody is the ideal do-it-all, cool-weather stretch shell. This hoody is built with a grid back that provides additional warmth and breathability, plus a wind and water-resistant coating that adds some midlayer warmth and abrasion resistance. A 1/4 zip design with a single chest pocket and two hand pockets, the Coefficient Storm can also pack into its front hand pocket when the sun hits.