Recent National Weather Service and model guidance indicate Seattle will clear after Friday's rain, setting up mostly sunny conditions and radiational cooling overnight into September 27. Forecast lows cluster near 45–47°F, driven by light winds, clear skies, and a post-frontal air mass that remains cooler than seasonal normals. This range sits near the boundary between several market bins, sustaining tight odds between outcomes above 60°F and those at or below 41°F. Marine air influence and variable cloud timing introduce modest uncertainty, while historical September minimums average around 51°F. Traders will watch updated model runs and NWS briefings for shifts in overnight low expectations before resolution.