Trader consensus on Singapore’s highest temperature for September 22 centers on the 31–33°C range, led by 32°C at 43.5% implied probability, reflecting Meteorological Service Singapore forecasts of 33–34°C maxima under prevailing southwest monsoon conditions with localized afternoon thundery showers. These showers, driven by regional convergence and high humidity, typically cap daytime peaks while allowing brief hot spells if convection is delayed or limited, consistent with the month’s pattern of frequent 33–34°C readings and occasional 35°C outliers. Model guidance shows modest spread, with some projections favoring slightly lower values near 31°C amid increased cloud cover, introducing uncertainty typical of tropical diurnal variability. Resolution hinges on official station measurements, with fresh updates expected from daily MSS briefings as the date approaches.