**Recent National Weather Service and model guidance positions the overnight low for Seattle on August 27 in the mid-to-upper 50s°F, centering market-implied odds on the 58-59°F bin (50.0%) followed by 56-57°F (38.5%).** Clear to partly cloudy skies overnight, combined with light southwesterly winds shifting lighter after midnight, will support moderate radiational cooling under the lingering marine layer. This setup typically produces lows near or slightly above the 1991–2020 climatological average of 55.9°F for the date, especially after daytime highs in the low-to-mid 70s that limit extreme surface cooling. Ensemble and deterministic model runs show limited spread around 56–59°F, with the highest-probability range aligning directly with the current leading outcomes; only a notable increase in cloud cover or a stronger onshore flow would push the low into the lower 50s, while warmer advection remains unlikely given the stable pattern. Updated NWS zone forecasts and hourly guidance released on August 25–26 continue to reinforce this range, anchoring trader consensus ahead of the overnight period when the daily minimum is typically observed.