**Trader sentiment for the lowest temperature in Panama City, Panama, on September 19 reflects genuine uncertainty in overnight cooling under typical wet-season conditions.** Current forecasts from regional models indicate a nighttime low near 24°C, with market-implied odds clustered tightly around 23–28°C because small differences in cloud cover, humidity, and convective activity can shift the minimum by 1–3°C. In Panama’s tropical maritime climate, September features high moisture from the ITCZ, frequent evening showers, and dew points often above 23°C that limit radiational cooling. Clear or partly cloudy skies after sunset promote greater heat loss and lower minima near 23°C, while persistent cloud decks or late showers trap longwave radiation and hold temperatures closer to 26–28°C. Recent observations show stable easterly flow with no strong synoptic forcing, so resolution hinges on the precise timing and coverage of nocturnal convection—variables that diverge across ensemble members and keep probabilities for the leading outcomes nearly even.