Watch: Incredible display of noctilucent clouds just before dawn

If you happened to be up early enough to beat the super early sunrise Thursday morning and looked up, you would have been treated to an incredible show of noctilucent clouds.

Greg Johnson's cameras at SkunkBayWeather.com were running and captured what was easily the best show of the year so far:

Noctilucent (as in "night shining") are caused by ice crystals coalescing around smoke particles left over from tiny meteors burning up upon hitting the Earth's atmosphere.

"The smoke trails then disperse over time and then, as the northern hemisphere heats up in late spring, ice crystals begin forming around those meteor smoke particles," Steve Rosenow, an astronomy photographer with Loowit Imaging in Shelton, told me in a previous weather blog. "When the sun is between 6-16 degrees below the horizon (or roughly one and a half times the width of your hand with your arm extended out), it lights the underside of those smoke particles. This gives them an otherworldly, electric-blue glowing appearance."

These clouds hang out in the upper reaches of the atmosphere at around 100,000 feet high -- well above where most weather clouds sit up to 40,000 feet.

They only appear within an hour or so after sunset or before sunrise, because the sun needs to be just below the horizon relative to you to darken the skies, but close enough to the horizon that it still lights up objects 100,000 feet high. They are also usually only spotted in the weeks around the summer solstice.