Abstract: An interlocking roofing panel is disclosed. The panel has longitudinal edges and large and small dikes extending along these edges. These dikes interlock to form a standing seam. Upon installation, the top wall of the small dike is sufficiently spaced below the top wall of the first dike of an overlapping longitudinally adjacent panel, defining an "upper gap," to interrupt movement of water between the dikes. Also, the small dike features a concave portion which opens towards the primary panel portion and the first dike has a linking portion, so that the linking portion extends into the concave portion while being sufficiently spaced within the concave portion, defining a "lower gap," that, during installation, upward movement of the first dike relative to the small dike is permitted.