Ongoing southwest monsoon (habagat) activity and associated cloud cover plus scattered showers and thunderstorms represent the dominant factors capping Manila’s daytime maximum on September 8. Multiple model runs and PAGASA guidance indicate highs clustered near 28–30 °C under persistently overcast skies and moderate southwesterly flow, with convective timing and intensity introducing the main spread between these outcomes. Recent heavy rainfall episodes have further moistened the boundary layer and reduced insolation, lowering the likelihood of brief clear spells that could push readings toward 31 °C or above. Traders appear to weigh the balance between model consensus on monsoon strength and the inherent variability of tropical convection when assigning the narrowest implied probabilities to 28–29 °C. Updated PAGASA bulletins and next model cycles will refine these thresholds ahead of resolution.