The Chihuahuan Desert To cope with July days on the Chihuahuan Desert, I was wearing a versatile Olympia jacket featuring four large zip-down panels (2 in front, 2 in back…) which cleverly rolled down to convert to a mesh jacket. But the key to the system was the evaporate cooling vest. While many of us may soak down a T-shirt in warm weather, the effect seems to last mere minutes. The quilted vest however, holds water like a camel, providing hours of relief. When it’s hotter than hell, this piece of equipment will elevate you to a tolerable purgatory.