Recent National Weather Service and ensemble model guidance indicate mostly sunny skies and light northerly winds over Seattle on October 8, supporting daytime highs in the upper 60s to low 70s under a ridge of high pressure. This setup favors radiative warming with limited marine cooling, though slight variations in cloud timing or wind direction across runs explain the near-even market odds on 68–69°F, 70–71°F, and 72–73°F bins. October climatology shows an average high near 63°F, so the current warm anomaly reflects the primary short-term driver, with updated model cycles expected to refine resolution thresholds before the date.