Forecasts for Metro Manila on August 21 show overnight lows centered near 26–28°C amid the southwest monsoon, with historical August averages around 25°C and trader-implied probabilities clustering tightly on 23–28°C outcomes. Persistent high humidity (75–95%), extensive cloud cover, and moderate southwesterly winds limit radiative cooling overnight, keeping minimum temperatures from falling sharply. Recent weakening of Typhoon Neneng into a low-pressure area has reduced rainfall intensity and allowed lighter cloud patterns, creating modest uncertainty in how much further cooling might occur before dawn. Heavier overnight showers or thicker low-level clouds would support higher minima near 27–28°C by trapping heat, while any clearing would favor the lower end of the range through enhanced longwave radiation loss. Updated PAGASA guidance and model runs through the morning will clarify resolution thresholds.