Siding panel with varying profile and siding system

The present disclosure relates generally to building surface panels, for example, polymer siding suitable for covering the exterior surface of a building. The present disclosure relates more particularly to a siding panel having a depth extending from a rear elevation to a front elevation. The siding panel includes a fastening strip at the upper side, an upper lock adjacent to the fastening strip, a lower lock at the lower side, and a panel body extending from the upper lock to the lower lock. The panel body has a contoured profile including an upper edge that is disposed at the front elevation and abuts the upper lock, a lower edge that is disposed at the front elevation and abuts the lower lock, and a first section disposed between the upper edge and the lower edge that projects toward the rear elevation of the siding panel to a first trough.