👀 Dual roll clouds seen in Fenwick Island, Delaware Via National Oceanic and Atmospheric Administration (NOAA): A low, horizontal tube-shaped arcus cloud associated with a thunderstorm gust front. Roll clouds are relatively rare; they are completely detached from the thunderstorm base or other cloud features, thus differentiating them from the more familiar shelf clouds. | WBRZ Chief Meteorologist Dr. Josh Eachus

Arcus cloud, Roll clouds Shelf clouds - menacing thundercloud moving over trees in stormy summer day with hot weather. Visible thunderstorm with wind and rain.

A shelf cloud (or arcus cloud) making its way toward our office just a little before 9 PM this Tuesday evening, leading in the next narrow line of showers and gusty winds. https://cloudatlas.wmo.int/en/clouds-supplementary-features-arcus.html | US National Weather Service Spokane Washington

Arcus Clouds: What They Are And How They Form

Bulgarian Arcus 98DA 9mm 4.66" 15 1 HG1014-N

Double Bass - Arcus bows (S series)

Bass Bows