Current forecast models from the European Centre for Medium-Range Weather Forecasts and Global Forecast System indicate a likely daily maximum temperature of 28–30 °C in Guangzhou on May 18, with ensemble spreads centered near 29 °C under partly cloudy conditions and light southerly flow. This positioning reflects the city’s subtropical monsoon climate, where May climatological averages hover around 29 °C, and short-term variability arises primarily from afternoon convection timing, urban heat-island effects, and boundary-layer moisture. The tight clustering of market-implied probabilities across 28–30 °C captures the modest uncertainty range typical of 24–48-hour temperature predictions, where small shifts in cloud cover or wind speed can alter peak readings by 1–2 °C. Updated model runs expected overnight will further refine the most probable outcome ahead of the daily maximum measurement.