Recent National Weather Service and private model guidance for Seattle on September 8 centers on mostly clear skies under northerly flow, supporting a daytime high near 72°F with light winds limiting mixing and marine-layer intrusion. This aligns with the September climatological average of 72.4°F at Sea-Tac while recent days’ 69–74°F readings and minimal precipitation have kept short-term trends stable. Traders assign the highest implied probability to 74–75°F because localized urban heating or slight model warm biases could push the official maximum into that bin, while the near-even split with 72–73°F reflects genuine uncertainty in exact peak timing and measurement site differences. Updated afternoon model runs and any unexpected cloud increases remain the key near-term variables that could shift resolution odds.