Official temperature observations from National Weather Service stations in Denver recorded a daily maximum of 82–83°F on September 26, 2026, producing the market’s near-certain outcome. Direct surface measurements, verified through standard instrumentation and quality-control protocols, aligned with regional forecast guidance issued by the National Weather Service in the preceding days. Model consensus had narrowed sharply as the event window closed, with ensemble runs showing minimal spread around that range. Only an undetected instrument malfunction or post hoc data revision—both statistically rare—could alter the recorded high before final market resolution.