Casting Time 1 standard action
Targets one or more Medium creatures/level, no two of which can be more than 30 ft. apart
1 This information missing from source material. Sean K. Reynolds addressed this question here. This is an unofficial response though.
You create a mobile cylinder of wind encompassing every target of the spell and protecting them as wind wall, but not interfering with them in any way. For example, arrows and bolts fired at the targets are deflected upward and miss, but the targets’ own arrows or bolts pass through the wall as if it were not there.
A Large creature counts as 4 Medium creatures for the purpose of how many targets you can effect with the spell; a Huge creature counts as 8, a Gargantuan creature as 16, and a Colossal creature as 32. This spell has no effect within the area of a higher-level wind or weather spell.
Section 15: Copyright Notice – Pathfinder Roleplaying Game Ultimate Magic
Pathfinder Roleplaying Game Ultimate Magic. © 2011, Paizo Publishing, LLC; Authors: Jason Bulmahn, Tim Hitchcock, Colin McComb, Rob McCreary, Jason Nelson, Stephen Radney-MacFarland, Sean K Reynolds, Owen K.C. Stephens, and Russ Taylor.