This was
your sky.

Mammatus Clouds Over Mexico

Mammatus clouds, like those pictured over Mexico, appear as bubble-like formations on cloud bottoms. Normal cloud bottoms are flat because rising moist air condenses into water droplets at a specific temperature and height. Mammatus clouds form when cloud pockets contain large water droplets or ice that fall into clear air as they evaporate. These pockets often occur in turbulent air near thunderstorms.