Types of severe storms
In addition to supercells, the atmosphere generates a number of different types of severe storms. A large class of these storms are called Mesoscale Convective Systems. They appear in many forms and include:
- Squall lines
- Bow Echoes
- Derechoes
- Mesoscale Convective Complexes
Squall Lines
- A squall line may be thought of as any line of convective cells.
- It may be a few tens of kilometers long or 1000 km long (>500 nm)
- there is no strict size definition.
- Squall lines are usually composed of a series of ordinary cells spread along and behind the leading edge of the system.
- However, a squall line may also be composed of a series of supercells.
- Behind the leading edge of the squall line is often an extensive region of stratiform precipitation.
QUESTION FOR THOUGHT:
Explain why squall-line thunderstorms often form ahead of advancing cold fronts but seldom behind them.
