**Trader sentiment heavily favors a minimum temperature of 29–30°C in Hong Kong on August 13, 2026, with market-implied probabilities of 74% for 30°C and 22% for 29°C.** This reflects the strong influence of ongoing summer conditions driven by a persistent southwesterly airstream over the South China Sea and Guangdong coast, which maintains high humidity and limits nocturnal radiative cooling. Official Hong Kong Observatory guidance and consensus forecasts project a daily range of roughly 29–34°C, with overnight lows held near 28–29°C amid sunny periods and only isolated showers. Urban heat-island effects and typical August climatology—where average lows hover around 26–28°C but trend higher under above-normal seasonal outlooks—further support these outcomes. Model consensus shows limited variability, with no incoming cold surge or significant rain event expected to drop temperatures below 28°C before dawn. Recent observations from automatic stations early on August 13 already register values near 30°C in urban areas, consistent with the slow overnight decline anticipated under the current regime. The narrow spread in leading probabilities underscores trader recognition of these stable atmospheric drivers and the low likelihood of atypical cooling on this date.