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Meteorology
3.9.4.1 Heat thunderstorms
Heat thunderstorms are one of the
most common types of
thunderstorms.
They occur on sunny days due to the
warming of the air near the ground.
They often form in the afternoon in
warm sectors (humid air).
Before a heat thunderstorm, the air often feels humid and oppressive.
Heat thunderstorms are typically local events that occur when the temperature
is highest, i.e., a few hours after noon.
3.9.4.2 Advection thunderstorms
Advection thunderstorms occur when a cold, humid air mass flows over a
warmer surface, causing instability in the air layers.
These storms occur in the summer over land and in the winter over water. The
thunderstorms are isolated and can usually be avoided.
3.9.4.3 Orographic thunderstorms
Orographic thunderstorms occur when a conditionally stable or unstable air
mass flows over a sloped surface, such as a mountain range.
3.9.4.4 Warm front thunderstorms
Warm front thunderstorms develop
when a conditionally stable warm air
mass becomes unstable as it slides up
over a front surface.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 328
