Weather phenomena

Cumulonimbus (CB)

the towering storm cloud associated with thunderstorms and severe turbulence

Anvil

the flat, spreading top of a mature thunderstorm cloud

Lightning strike

an electrical discharge, capable of hitting an aircraft in flight

Fog bank

a dense, well-defined mass of fog reducing visibility near the ground

Freezing fog

fog at sub-zero temperatures that deposits rime ice on exposed surfaces

Rime ice

rough, opaque, milky ice formed from small supercooled droplets freezing on contact

Clear ice (glaze)

smooth, dense, transparent ice

Wind shear

a sudden change in wind speed or direction over a short distance

Microburst

a violent, localised downdraught

Gust front

the leading edge of cold air spreading out ahead of a thunderstorm

RVR (Runway Visual Range)

the measured distance a pilot can see down the runway in low visibility

Squall

a sudden, sharp increase in wind, often accompanied by rain or snow