What is a pulse storm?
A pulse storm is a thunderstorm that produces strong to severe weather in a short period of time. The environmental conditions conducive to pulse storms are strong CAPE and weak wind shear. The strong CAPE contributes to a strong thunderstorm updraft. Strong and severe thunderstorms often have strong updrafts associated with them. The weak wind shear is what causes the duration of the storm to be small. Contributing to weak shear are weak upper tropospheric winds and weak winds within the troposphere in general. Since the shear is weak, the downdraft will fall into the vicinity of the updraft and cut off the inflow into the updraft. The downdraft will also reduce the momentum within the updraft.
