Recent ensemble forecasts from Argentine meteorological agencies and global models point to a maximum temperature of 15–17°C in Buenos Aires on May 18, reflecting the close clustering of market-implied probabilities around those outcomes. Late-autumn high pressure and moderating southerly flow have kept daytime maxima near the seasonal average of 17°C, with limited diurnal warming expected under partly cloudy skies. Minor differences among leading scenarios arise from small variations in boundary-layer moisture and the timing of any weak frontal passage, which could trim or boost the peak by 1°C. Official observations from the city’s central station will resolve the market once the full 24-hour period ends.