**Recent NWS and local forecast updates indicate mostly sunny skies and a modest warming trend for August 11, supporting trader emphasis on the 70-71°F bin.** San Francisco’s summer temperatures are tightly constrained by the persistent marine layer, strong onshore westerlies, and coastal upwelling that typically cap highs near the 69°F August average. Model consensus and recent observations show reduced cloud cover and lighter winds allowing afternoon readings to edge into the low-to-mid 70s at downtown and airport stations, while any stronger marine push or earlier fog could hold readings at 68-69°F. The close 37%–28% split between these two outcomes reflects genuine forecast uncertainty around the exact timing and strength of the sea breeze and marine-layer depth on this short time horizon, with higher bins priced low due to the region’s climatological ceiling.