Weather Stasis

Weather stasis maintains the weather conditions prevalent in the area of effect when the spell is cast. The spell affects a cube whose sides equal the caster's level times 10 feet (a 10th-leveI caster could affect a 100' x 100' x 100' cube).
An area protected by weather stasis is unaffected by temperature variations in the surrounding environment. The spell also acts as a shield against rain, snow, and hail, which cannot enter the protected area. If conditions of precipitation existed in the area of effect when the spell was cast, the identical weather will continue for the duration of the spell.
For example, weather stasis is cast in an area where the temperature is 75° F. and no precipitation is falling. Half an hour later, the temperature drops to 60 degrees and rain begins to fall. The protected area remains dry and the temperature stays at 75 degrees. If the spell had been cast while rain was falling in the area of effect, rain would continue to fall for the duration of the spell, even after it stopped raining in the surrounding area.
All physical objects other than rain, snow, and hail can pass into the protected area. All creatures and characters can move freely into and out of the area. The spell does not prevent water-based spells or water-based creatures (such as water elementals) from operating in the area.
The spell protects against both natural and magically generated weather. Night and day pass normally in the protected area, although temperature variations associated with night and day do not occur.

[Tome of Magic]

Sphere: Wards, Weather
(Abjuration)
Level: 4

Range: 30 yards
Components: V, S, M
Duration: 1 hour/level
Casting Time: 1 turn
Area of Effect: 10-foot cube/level
Saving Throw: None

Material Components:
the priest's holy symbol and a drop of rain