Look west 30 to 60 minutes after sunset when the Sun has dipped 6 to 16 degrees below the horizon. If you see luminous blue-white tendrils spreading across the sky, you’ve probably spotted a noctilucent cloud. Although noctilucent clouds appear most often at high latitudes–e.g. places like Scandinavia and Canada–they have been sighted as far south as Colorado, Utah and Virginia.
Noctilucent Clouds
Look west 30 to 60 minutes after sunset when the Sun has dipped 6 to 16 degrees below the horizon. If you see luminous blue-white tendrils spreading across the sky, you’ve probably spotted a noctilucent cloud. Although noctilucent clouds appear most often at high latitudes–e.g. places like Scandinavia and Canada–they have been sighted as far south as Colorado, Utah and Virginia.