Will this product work on the exterior of a skylight where temps can range from 90�F down to -20�F?

This product is very durable and is warrantied for exterior use. When using on a sloped skylight, it may be beneficial to use a thin bead of clear silicone caulk to help ensure the integrity of the edges over time. This can be done once it has cured for a few days. It's not required, but we do recommend on all exterior installs for longer lasting results.