Rare Clouds: Nacreous Clouds

Nacreous clouds are clouds that form in the very cold conditions 10-15 miles above the Earths surface. This would place them in the lower stratosphere, unlike their cousin the iridescent cloud which is formed in the troposphere. The nacreous clouds are much brighter and defiantly more colorful than iridescent clouds. Mainly seen during the winter at high latitudes, they happen to be fairly rare. The best place to see them is Scandinavia, Iceland, Alaska and Northern Canada. The clouds are brightest just after sunrise or before dawn.