Recent forecasts from NOAA and private models indicate an upper-level low driving widespread rain and persistent cloud cover into Sunday morning in Seattle, limiting overnight radiative cooling and supporting minimum temperatures in the low-to-mid 50s°F. Southerly flow and elevated dew points from the marine layer further moderate extremes, consistent with historical September averages near 53.5°F. Model spreads arise mainly from the precise timing of heaviest precipitation and wind gusts, which can shift the overnight low by a few degrees. Trader odds cluster tightly around 52–55°F bins because current guidance shows limited potential for either strong cold advection or clear-sky radiative drops below 50°F, while warmer outcomes remain plausible if showers clear earlier than expected. Updated NWS briefings and next model runs will refine these thresholds ahead of resolution.