Hard to tell seeing how the cloud was basically above me but i think i might have captured a pileus cloud from close range.
A thunderstorm can be described as being ‘severe’ when one or more of a number of criteria is met. The winds gusts have to reach or exceed 57.5mph (92kph), hail greater than 19.1mm (0.75 inches) in diameter is produced or tornadoes have to be generated.