Storm clouds

Cumulonimbus clouds

Cold rain process

Saturated vapour pressure

Ice crystals grow at the expense of supercooled water droplets.

Air is saturated over ice.

Air is not saturated over water.

Water evaporates from the supercooled droplets - the droplets disappear

The water vapour deposits on the ice crystals - the crystals grow

Falling ice particles

Development of cumulonimbus

Multi-cell storm

Thunder and Lightening

Lightening

Forked lightening from cloud, showing stepped leaders and main return stroke

Lightening originating from a tower on the ground, note forks go upwards.

Time resolved lightening formation

Supercell thunderstorm

Contrails

At high altitude ~10 km temperature very low, condensation aided by exhaust particulates and vortices.

Nacrecous clouds

Nacrecous clouds are 15 - 25 km high, in the stratosphere well above tropospheric clouds, and occur mostly in polar regions and in winter at high latitudes. Seen after dusk.Also called mother-of-pearl or polar stratospheric clouds.

Noctilucent clouds

Noctilucent clouds are thought to be composed of small ice-coated particles; their precise nature remains a mystery. They form at very high altitudes ~ 82 km - and are a quite separate phenomenon from normal tropospheric clouds.