**Forecast consensus points to a high near the September climatological average of ~32°C for Guangzhou, with model spreads and local convective potential creating the observed market distribution.** Multiple sources, including ECMWF-influenced outlooks and local agencies, currently project a maximum of 32–33°C on September 12 under mostly cloudy to thundery conditions, consistent with typical late-summer monsoon patterns in the Pearl River Delta. Afternoon thunderstorms or increased cloud cover—common in this season—can limit peak heating by reducing insolation and enhancing evaporative cooling, while clearer periods or stronger subsidence could allow readings to reach 34–35°C. Humidity remains high (often 50–70%), supporting elevated heat indices even if the dry-bulb maximum stays moderate, and steering winds from the northeast or variable directions influence boundary-layer mixing. Historical data show September 12 highs averaging 32.3°C with a record of 35.8°C, so the tightly bunched probabilities around 30–37°C reflect genuine short-range uncertainty from timing of any showers rather than a broad shift in the large-scale pattern. Updated model runs and official briefings from the China Meteorological Administration over the next 24–48 hours will likely narrow the range ahead of market resolution.