**Trader sentiment for the highest temperature in NYC on August 21 reflects tight clustering around 76–81°F, driven by official forecasts and model guidance showing a cooler-than-average day for late summer.** National Weather Service point forecasts and matrices indicate a maximum near 80–81°F under mostly sunny to partly cloudy skies, with lows in the upper 60s, consistent with recent model runs incorporating northeasterly flow and modest moisture. This places the highest probability on the 78–79°F and 80–81°F bins, which together hold over half the market-implied odds. Slight downward pressure on the upper bins stems from potential for increased cloud cover or a weak frontal boundary limiting daytime heating, while historical August 21 averages near 83°F provide context for why traders see downside risk relative to climatology. Key variables differentiating the closely matched leading outcomes include small differences in afternoon mixing, dewpoint trends, and exact timing of any sea-breeze effects, all of which can shift the observed high by 2–3°F. With resolution imminent, traders are weighting the latest NWS updates and ensemble consensus most heavily.