National Weather Service forecasts and ensemble models currently indicate a minimum temperature near 58°F for San Francisco on August 22, consistent with the marine layer’s typical depth and onshore flow that limits overnight radiational cooling under partly cloudy skies. Persistent high pressure offshore and a compressed marine inversion have kept recent lows in the mid- to upper 50s, aligning with August climatology of 57°F at official stations. Differentiation among the closely matched 56–57°F and 58–59°F bins hinges on subtle variations in cloud cover, wind speed, and exact measurement timing at the airport sensor, where even modest increases in mixing or fog dissipation could shift the observed minimum by 1–2°F. Traders are weighting these near-term model runs against historical analogs showing limited day-to-day volatility in late-summer coastal regimes.