Severe Thunderstorms

  • Often thunderstorms are severe, producing hail, damaging surface winds, flash floods and tornadoes
  • The NWS defines a severe thunderstorm as one that produces 3/4" hail and/or surface wind gusts of 50 knots.
  • severe thunderstorms form in an environment characterized by:
    • large instability
    • large amounts of environmental vertical wind shear. Vertical wind shear is when the winds increase in strength with height
  • severe thunderstorms usually extend all the way to the tropopause and can be seen in satellite imagery as storms producing overshooting tops.

Types of severe storms

The atmosphere generates a number of different types of severe storms. Some examples include:

  • Supercell thunderstorms
  • Squall lines
  • Mesoscale Convective Complexes
  • Bow Echoes
  • Derechoes