Chengdu's late-August climate typically features daytime highs of 30–35°C under the influence of the western Pacific subtropical high, with the Sichuan Basin's topography trapping heat and moisture to sustain humid conditions and elevated heat indices. Current extended forecasts for August 21, 2026, point to maximum temperatures near 33–34°C amid partly cloudy skies and scattered showers, consistent with seasonal norms where afternoon convection can briefly moderate peaks. Official monitoring from agencies like the China Meteorological Administration emphasizes model consensus on minimal cooling fronts through the period, though variability in rainfall timing remains a key uncertainty affecting daily maxima. Historical analogs show occasional excursions above 35°C when subsidence strengthens, underscoring the narrow window for traders assessing threshold probabilities.