Trader consensus for the highest temperature in Buenos Aires on May 18 centers on 16–17°C, as latest ensemble forecasts from global and regional models converge on mild autumn conditions driven by a southerly airflow that advects cooler maritime air from the South Atlantic. This setup, combined with variable cloud cover that limits daytime solar heating, keeps peak values below the seasonal climatological average of around 18–19°C. Persistent light winds further suppress local warming, consistent with recent observations showing stable high-pressure influence rather than any warm advection. Key uncertainties remain tied to exact cloud timing and minor model spread in boundary-layer mixing, with final National Meteorological Service updates expected to clarify resolution thresholds before the day ends.