**Forecast models from the National Weather Service, WeatherBug, and other sources project an overnight low in the mid-70s°F for Chicago on August 30, 2026, under a warm, humid air mass with southerly flow.** This places the highest market-implied probabilities on the 70–73°F bins (28% each), as traders weigh the consensus around 74–75°F against potential for slightly greater radiational cooling if skies clear more than expected. A slight chance of showers or thunderstorms could limit nighttime temperature drops by trapping heat and increasing cloud cover, while the lack of an approaching cold front keeps minimums well above the long-term average low of ~64°F. Uncertainty in exact minimums arises from variables like dew point trends, wind speeds, and timing of any cloud breaks, which explains why probabilities remain distributed across nearby ranges rather than converging on one outcome. Updated model runs closer to the date will refine these estimates.