As an Amazon Associate I earn from qualifying purchases. ? Handheld Weather Station: https://amzn.to/3O1AaeK ? Storm Lightning Detector: https://amzn.to/2OPRlzv ? Storm Chasing Handbook: https://amzn.to/2OnPyCQ ? Glass Mount Antenna: https://amzn.to/2RJzDBu ? Rain-X Windshield Rain Protection: https://amzn.to/2W7ENbB Thunderstorm damage as winds knock down power lines in front of me. A wall cloud is a large, localized, persistent, and often abrupt lowering of cloud that develops beneath the surrounding base of a cumulonimbus cloud and from which tornadoes sometimes form. It is typically beneath the rain-free base portion of a thunderstorm, and indicates the area of the strongest updraft within a storm. Rotating wall clouds are an indication of a mesocyclone in a thunderstorm; most strong tornadoes form from these. Many wall clouds do rotate; however, some do not. Genesis Wall clouds are formed by a process known as entrained, when an inflow of warm, moist air rises and converges, overpowering wet, rain-cooled air from the normally downwind downdraft. As the warm air continues to en train the cooler air, the air temperature drops and the dew point increases (thus the dew point depression decreases). As this air continues to rise, it becomes more saturated with moisture, which results in additional cloud condensation, sometimes in the form of a wall cloud. Wall clouds may form as a descending of the cloud base or may form as rising scud comes together and connects to the storm's cloud base. ... https://www.youtube.com/watch?v=8kt9fYadrVM