Official observations from National Weather Service stations in Seattle recorded a daily high temperature of 58–59°F on May 16, anchoring trader consensus at near-certainty for that outcome. Persistent marine layer clouds and onshore flow from the Pacific suppressed daytime heating, keeping conditions close to the long-term May average of around 60°F. Surface analyses and regional model guidance showed no warm-air advection or clear-sky periods that would have pushed readings higher. This positioning reflects verified instrumental data rather than forecasts, though minor post-event adjustments at specific stations or microclimate variations could theoretically alter the official record.