National Weather Service forecasts for Houston on August 21 indicate an overnight low near 81°F under persistent high pressure, southerly flow, and dew points in the mid-70s that limit radiative cooling and promote urban heat retention. This aligns with late-August climatology, where average lows hover around 77–78°F but often stay elevated during humid periods with minimal wind mixing or cloud cover. Trader sentiment clusters around 80–81°F as the mode because model consensus shows little deviation from these conditions, though slight variations in timing of any sea breeze or brief clearing could nudge readings into the 78–82°F range. Lower outcomes remain discounted absent an unexpected frontal passage or measurement anomaly at official stations.