Trader consensus on a 70-73°F high for San Francisco on June 17 centers on the persistent marine layer and moderate onshore flow typical of early summer along the central California coast. Official National Weather Service guidance and model consensus indicate morning low clouds with partial afternoon clearing under light southwest winds of 10-20 mph, limiting insolation and keeping maximum temperatures near or slightly above the 72°F daily normal at SFO. Recent days featured highs in the low 70s with minimal heat advection from interior valleys, while stronger upwelling and a stable boundary layer have suppressed the brief warming episodes seen earlier in June. The narrow spread between the two leading bins reflects uncertainty in exact clearing timing and local microclimate effects at the official reporting station, with any delayed marine intrusion favoring the lower range.