Recent forecasts for Buenos Aires on September 19 point to mild spring highs near 22–24°C under building high pressure and light easterly or northeasterly winds, with limited cloud cover allowing moderate daytime heating but moderated by onshore flow from the Río de la Plata. Trader consensus clusters tightly around 22–25°C because global models show only minor differences in afternoon insolation and boundary-layer mixing, while historical September averages hover near 18–20°C. Key variables that could shift the exact peak include any increase in low-level stratus or a slight strengthening of the sea breeze, both of which would cap temperatures below 24°C; conversely, clearer skies or a brief northerly component could push readings toward 25°C. Updated model runs and official Servicio Meteorológico Nacional guidance expected in the next 24–48 hours will likely narrow these probabilities.