The official National Weather Service climate summary for Seattle-Tacoma International Airport recorded a maximum temperature of 68°F on October 5, 2026, at 3:03 PM local time, driving the market's 100% implied probability on the 68-69°F bin. This value exceeded the 1991-2020 normal high of 65°F by three degrees amid dry, partly sunny conditions with light northerly winds and relative humidity dropping to 65% in the afternoon. Traders priced the outcome based on real-time observational data from the primary reporting station, consistent with regional patterns of mild early-October highs following an unusually cool September. Resolution criteria tied to this verified measurement leave little room for revision unless official post-analysis adjustments occur, which historical precedents show are rare for daily extremes.