A flange mounted weatherseal includes a carrier and a flexible cover covering the carrier. The carrier includes a base portion, a first side portion and a second side portion generally parallel to the first side portion and cooperating together with the first side portion and the base portion to define a generally U-shaped channel. The first side portion defines a plurality of first fingers, the second side portion defines a plurality of second fingers opposite the first fingers along a longitudinal axis, and the base portion defines a plurality of webs offset along the longitudinal axis relative to the first fingers and the second fingers. The first fingers, the second fingers and the webs each include deformations defining a non-planar cross sectional shape along the longitudinal axis to increase the rigidity of the carrier.