Trader consensus on Polymarket shows a razor-thin split favoring 62-63°F (39.5%) over 60-61°F (36.5%) for San Francisco's highest temperature today, reflecting inherent uncertainty in National Weather Service forecasts calling for a high near 65°F under mostly sunny skies with west winds of 7-11 mph. Cool Pacific sea surface temperatures around 55°F sustain a persistent marine layer of coastal stratus clouds, often delaying morning fog burn-off and capping diurnal heating in the low 60s at official stations like KSFO; however, stronger afternoon solar insolation amid lighter onshore flow could nudge peaks toward mid-60s. Recent days featured cooler-than-average highs (e.g., 55°F on April 9), but warming trends and model consensus point to this tight range. Hourly observations through evening will clarify resolution.