In spring and autumn, special clouds line up in streaks and strips. These clouds are created by gravity waves and indicate changing weather and strong winds aloft.

Gravity waves are created when air is forced to oscillate in a stable layer of the atmosphere, usually above cold air masses or at the centers of high-pressure systems. Like ripples in water when a rock is thrown into it, waves of clouds and clear spots are created.

They come in all kinds of sizes. Small gravity waves often appear on the underside of stratus clouds downwind of the Appalachian and Rocky Mountains. Larger gravity waves appear on the WeatherRadar as large parallel lines, almost like zebra stripes.

See how these look from the surface in the video:

Check out the WeatherRadar to see if you can find these clouds.