A roof rack assembly includes first and second roof rails spaced from one another, each roof rail having a respective deployable roof rack bow and a respective drive mechanism operatively connected to the roof rack bow that causes the roof rack bow to extend in length by a predetermined amount when pivoted from a stowed position to a deployed position and retract in length by the predetermined amount when pivoted from the deployed position to the retracted position. The predetermined amount that the bows extend when pivoted is sufficient to cause the respective roof rack bows to span from the first roof rail to the second roof rail when in the deployed position.