Forecast models from sources including the National Meteorological Service indicate a minimum temperature in Mexico City on August 28 likely falling in the 12–15 °C range, driving the tight clustering of market-implied probabilities around 13–15 °C. High elevation near 2,240 m promotes strong nighttime radiative cooling under clear skies, yet widespread cloud cover and scattered showers expected overnight will trap heat and moderate lows closer to the seasonal average of about 12–13 °C. Recent observations show similar conditions yielding minima of 12–14 °C, while model spread and variable precipitation timing create the narrow gap between leading outcomes. Traders are weighting ensemble consensus against historical late-August variability, with resolution hinging on official station readings.