People across Northern Virginia observed a rolling cloud passing over Monday morning.
On the leading edge of a cold front gliding through the D.C. metro region this morning, a scary-looking tube-shaped cloud stretched across the skies in northern Virginia. It ended up signaling mostly benign weather, in the form of some showers that followed its passage.
This cloud type is known as a roll cloud or arcus cloud.
A bit scary. The sky is big, it can destroy us. But this has an explanation. Enjoy the anomaly. Pretty cool. Check out the other pictures at the above link.