Abstract: A clamp-on cover for the top of a golf bag provides a vertical hemi-cylindrical shield extending the back of the golf bag in upward direction but preserving a half-circular arc of access to clubs laterally, and a helmet-shaped portion pivoted at the brim to a rear portion of the hemi-cylindrical shield near but not at the top provides for the helmet-shaped portion to rise when opened to either a fully open stable position clear of the club head area or to the half open position at which it serves as a concave, high clearance, overhanging roof which is self-closing, while overlapping and co-acting with the vertical hemi-cylindrical portion to shield against blowing rain.