Forecast models from the National Weather Service and NOAA consensus point to a minimum temperature in Chicago on August 28 near 64–66°F under clear to partly cloudy skies and light southerly winds. Stable high pressure and a mild air mass with dew points in the upper 50s to low 60s are limiting radiational cooling overnight, while recent observations from O’Hare show similar overnight lows in the mid-60s amid comparable conditions. Trader-implied odds clustered in the 60–65°F range reflect model agreement on these factors, with modest divergence possible if evening cloud cover increases or winds remain calm enough for additional cooling toward the lower end of the range. Updated NWS guidance and morning model runs on August 28 will provide the final data for resolution.