Weather Shield, Mass

School abjuration; Level druid 5, elementer 5, invoker 4, ranger 4, shaman 5, sorcerer/wizard 5
Targets one creature or object /level, no two of which can be more than 30 ft. apart

This spell functions As weather shield, except it affects multiple creatures or objects. Each affected object can weigh up to 20 pounds per caster level, and 50 pieces of ammunition counts as a single object.