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Meteorology

But it's not only the CB cloud itself that can be dangerous.

Many kilometers before the CB cloud, there can be a "gust front," where the

wind suddenly shifts direction and strength.

For instance, a plane can go from having a headwind of 20 knots to having a

tailwind of perhaps 60 knots. This has caused accidents for both small and large

aircraft!

3.6.4.2 Development of a CB cloud

A CB cloud has three stages: the development stage called “the Cumulus stage”,

the middle stage called “the mature stage”, and the final stage called “the

dissipating state".

Comulus Stage

The cloud draws in energy. Beneath the cloud, there are only updrafts. The

cloud rapidly grows over the 0°C isotherm.

Inside the cloud, there is rain and sleet. Updrafts range from a few hundred feet

per minute to 6000 feet per minute. By the end of this stage, strong icing and

turbulence have developed within the cloud.

The cloud is now about 15 minutes old.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 284