Recent forecasts from multiple models indicate the lowest temperature in Buenos Aires on September 26 will likely fall in the 11–15°C range, driven by southeasterly winds advecting cooler maritime air after a mild spring day on the 25th. Official guidance and ensemble runs show overnight cooling under increasing cloud cover and moderate easterly flow, with minimums potentially reaching the low teens Celsius by early morning. This positions the 10°C-or-below outcome as the market leader amid model spread on exact timing and boundary-layer mixing, while warmer scenarios reflect uncertainty if winds remain lighter. Historical September minima average near 10–12°C, providing context for current trader emphasis on near-term observational updates from the National Meteorological Service.