**Trader consensus has converged on a 12°C high for Buenos Aires on September 12, 2026, at essentially 100% implied probability because official station observations recorded a maximum of exactly 12°C.** Cold southerly winds and persistent cloud cover kept daytime readings suppressed, with forecasts from multiple models converging on a peak near or below 12–14°C and actual measurements confirming the lower end of that range. This aligns with the seasonal transition into spring, where September averages hover around 14–17°C but polar air intrusions can produce sharp drops. Resolution hinges on the precise maximum from the primary Buenos Aires weather station, and with the date now passed, no realistic scenario remains that would shift the outcome away from 12°C absent a major revision to verified data.