Cloud-watchers can talk all about the interesting shapes they've noticed over the years. They may have been gazing out the car window during a road trip, or tanning on the beach, or on a morning walk.

A “roll cloud” spotted off the coast of Portugal looked like something out of a movie. Here’s the science behind it.

Owen told me that the picture was simply of a sunset over Hawaiian ocean waters. Yep, that's it. It is not even volcanic activity as some have also reported.

The impact of the recent Saharan dust cloud was likely most severe in the Caribbean. Ordinarily, the concentration of PM10 is 10 to 20 micrograms per cubic meter of air, mostly due to sea salt.

The sky had an ocean wave look to it for a time yesterday. These rare clouds were spotted over southern Michigan Wednesday evening. The clouds are called Kelvin Helmholtz clouds, named after two ...

As stratocumulus clouds cover 20% of the tropical oceans and critically affect the Earth’s energy balance (they reflect 30–60% of the shortwave radiation incident on them back to space1 ...

Here’s what made D.C.’s sunset so dazzling on Thursday. A conveniently placed cloud deck, ... A conveniently placed cloud deck, perfect sun angle and ‘gravity waves’ played a role.