With a wide sweeping movement of your arms, you create a tunnel of pure wind energy.  This wind tunnel extends from the caster in a straight line up to its total range but does not pass through full cover.  A medium (or smaller) creature that jumps into the wind will be carried forward to the end of the wind tunnel.  It requires a strength save the exit the tunnel before reaching its full length equal to the spellcaster's spell save DC.

Any creature going against the wind will have their movement halved.  The windstream lasts until the end of the caster's next turn.  This cannot be used to raise a non-flying creature higher than 15 ft off the ground.