Singapore’s tropical climate during the Southwest Monsoon features persistently high humidity and light variable winds that limit nocturnal radiative cooling, keeping minimum temperatures typically in the mid-20s Celsius. Current official outlooks indicate partly cloudy to mostly clear skies overnight on August 31 with scattered thundery showers possible, conditions that produce modest cooling after daytime maxima near 30–31°C. Recent August minima have frequently stayed above 27°C amid below-average rainfall and warmer-than-normal nights, yet model spreads in cloud cover and timing of any showers introduce uncertainty around the precise low. This genuine variability in boundary-layer cooling and precipitation timing underpins the tight clustering of market-implied probabilities across 25–28°C.