**NWS point forecasts for San Francisco on September 18 indicate a high near 70–72°F, with patchy morning fog followed by gradual clearing and light west winds under persistent onshore marine flow.** This pattern aligns with climatological norms for mid-September, when the marine layer typically caps daytime warming despite seasonal solar input, producing afternoon maxima around the long-term average of 70.8°F. Model consensus shows limited spread, but small differences in fog clearance timing or boundary-layer mixing could shift the observed peak by 1–2°F across official stations. Trader positioning around the 70–73°F bins reflects this narrow uncertainty range, with capital-weighted odds incorporating both historical variability and the absence of anomalous synoptic forcing that might drive stronger heating or cooling. Updated NWS guidance and real-time observations tomorrow morning will refine the exact maximum used for resolution.