Measurements of the spatial coherence of high‐frequency sound forward scattered from the sea surface are discussed, along with a simple interpretive model. The data originate from an experiment off the southern California coast using the research platform FLIP. Measurements were made using omnidirectional sources suspended from a spar buoy (tethered to FLIP) and a line array mounted on FLIP’s hull; the range varied between 500 and 1000 m. The combination of high frequency and large surface roughness makes the roughness parameter χ ≫1. The spatial coherence was measured across a line array oriented transverse to the direction of propagation, thereby giving an estimate of the horizontal coherence. The data are interpreted with a model based on the geometrical‐optics limit of the Kirchhoff approximation, and a bubble scattering mechanism is also discussed. A concise expression is derived for the rms horizontal angular width σθhin surface forward scattering.