Cloudscape

A character can cast cloudscape on a single cloud or part of a cloud bank, usually from a nearby mountaintop or while flying. It causes 1,000 cubic feet of cloud per level of the caster to become solid enough to support any weight. The solidified clouds remain airborne and feel like a thick carpet.

A creature that falls onto the magically strengthened cloud sustains normal falling damage. An animal or individual that flies into the solidified cloud falls, stunned, for a round and must make a successful Dexterity check to recover. If a creature is flying through a cloud at the moment it becomes solidified, it may make a saving throw vs. petrification. Those who succeed escape the cloud in time. Creatures that fail the save become trapped as the cloud solidifies around them. However, as the cloud is porous, they can continue to breathe until the spell's duration elapses.

The solidified cloud itself continues to drift with the wind as usual. While the caster cannot use this particular spell to propel the cloud at all, a Control Winds spell can summon a great gust of air to turn the cloudscape into a unique flying conveyance easily enough.

[Complete Druid's Handbook]

Druidic

Sphere: Weather
(Alteration)
Level: 5

Range: 120 yards
Components: V, S
Duration: 3 turns/level of caster
Casting Time: 8
Area of Effect: 1,000 cubic feet/level of caster
Saving Throw: None