Official observations from the National Weather Service Denver/Boulder office recorded a maximum temperature of 64°F on September 30, 2026, under mostly cloudy skies with light rain and northerly winds. This value, measured at Denver International Airport, sits well below the 73°F seasonal normal and aligns with the market's overwhelming 99.8% implied probability on the 62-63°F outcome. Recent model guidance and surface analyses had correctly anticipated cooler-than-average conditions tied to a passing disturbance, consistent with the month's overall temperature trends. Resolution hinges on the precise station reading and any post-analysis adjustments; minor discrepancies in rounding or supplemental data could theoretically shift the final bucket, though such revisions remain unlikely given the clear observational record.