Official meteorological observations from Buenos Aires stations have confirmed a daily maximum of 17°C on September 30, driving the market's 100% implied probability for that exact outcome. Late-September climatology in the region typically features transitional spring conditions with moderate highs influenced by southerly flows and variable cloud cover, aligning with the recorded value and limiting upside potential. Model guidance from regional forecasts showed tight consensus around this range in the preceding 48 hours, with no significant warm-air advection or clear-sky amplification materializing. Resolution hinges on verified station data rather than models, leaving little room for revision unless post-analysis adjustments occur.