Current forecast models from NOAA and the National Weather Service indicate Seattle's overnight low on August 28 will likely settle in the mid-to-upper 50s, with marine air influence from Puget Sound and typical late-summer radiative cooling under variable cloud cover creating the tight clustering around 56–59°F. Ensemble spreads in GFS and ECMWF runs show modest uncertainty from wind speeds and humidity levels that could either enhance or limit surface cooling, while the urban heat island effect adds a small upward bias to minimum readings. Traders appear to weigh these factors evenly given the balanced probabilities, with any shift in afternoon sea-breeze patterns or unexpected clear skies likely to tip the outcome between the leading bins.