Official meteorological observations from Mexico City on June 4 recorded a daily maximum of exactly 25°C, aligning with typical early June highs at the city's high-elevation plateau under stable subtropical high-pressure conditions and moderate solar insolation. Long-term climatological averages place June peaks near 24–26°C, with minimal day-to-day variability absent strong frontal systems or moisture surges from the Pacific or Gulf. This data point from authoritative surface stations drove the market-implied odds to near-certainty for 25°C. Minor variations in microsite placement, instrumentation calibration, or timing of peak measurement could theoretically shift the recorded value by 1°C, though such discrepancies remain rare in standardized reporting.