In a brief paragraph please tell me how vertical air motion can cause severe storms.

Okay so, in a brief paragraph. The vertical air motion can cause severe storms. How they can is, vertical air motion which causes different things. It can cause severe air storms because it’s going vertical direction

A significant increase of wind speed with height will tilt a storm's updraft. ... Strong lower tropospheric winds and directional shear together will generate high values of Helicity and thus this increases the tornado threat when severe storms develop.