**Real-time meteorological observations from Helsinki-Vantaa and nearby stations established a daily maximum of 16°C on October 1, 2026, driving the market's near-certain 100% pricing on that outcome.** Clear to partly cloudy skies under high pressure, light southeasterly winds, and mild advection allowed afternoon readings to peak at this level, consistent with model guidance showing 14–16°C highs against a seasonal average of 12.3°C. Historical context places this above recent years but below the 17°C record. Minor post-hoc adjustments to official data remain theoretically possible yet improbable given convergent station reports and stable conditions through the resolution window.