1.1. Cauliflower clouds

Not all clouds produce thunderstorms, in fact, fairly few do so. You can spot clouds that indicate a thunderstorm may develop, is developing or has developed, just by looking at their general appearance. They look like cauliflower. Seriously. Cauliflower. Let us take a look at how and why thunderstorms form.                      Background image created by … Read more 1.1. Cauliflower clouds

1.1.1.1. The atmosphere – where do thunderstorms live?

THE ATMOSPHERE The thin shell of gas around our planet that we call our atmosphere is divided into several layers. While the pressure falls with increasing altitude, the temperature is more dynamic, alternately decreasing and increasing with altitude. The layers are: Troposphere [surface – ~12 km] Stratosphere [~12 – 50 km] Mesosphere [50 – 80 … Read more 1.1.1.1. The atmosphere – where do thunderstorms live?

1.1.2.1. Stable and unstable atmosphere

Stable and unstable atmosphere, instability Atmospheric stability is the resistance of the atmosphere to vertical motion of air. A stable atmosphere inhibits vertical motion. An unstable atmosphere encourages vertical motion. The stability depends on how the air temperature changes with altitude (the temperature lapse rate). Very stable: temperature increases with altitude, a temperature inversion. Air … Read more 1.1.2.1. Stable and unstable atmosphere

1.1.2.2. Initiation of convection – how thunderstorms start (daytime heating, fronts, etc)

Initiation of convection On a warm day, convection begins when the air close to the surface warms enough to become buoyant and start rising. This process is called free convection. The temperature at which free convection begins is called the convective temperature. When the convective temperature is reached on a clear, hot and humid day, … Read more 1.1.2.2. Initiation of convection – how thunderstorms start (daytime heating, fronts, etc)