At the north end of Salt Point State Park, Secrets (a.k.a. Horseshoe Cove) is a lefthand reef/point that works during S winds and winter swells. The name 'Secrets? is a misnomer, because everybody and their brother will be out surfing here when the S wind is howling offshore. It's a low tide spot, achieving prime shape with a larger W swell.
Beware of several submerged rocks and such. The take-off spot is small and the currents can be bad, but Secrets will probably provide you with your best Sonoma waves north of Salmon Creek (that is, if the Russian Rivermouth isn't happening). Camping nearby.