Highest temperature in Chicago on August 18?
- Will the highest temperature in Chicago be 71°F or below on August 18?<1¢
- Will the highest temperature in Chicago be between 72-73°F on August 18?<1¢
- Will the highest temperature in Chicago be between 74-75°F on August 18?<1¢
- Will the highest temperature in Chicago be between 76-77°F on August 18?2¢
- Will the highest temperature in Chicago be between 78-79°F on August 18?19¢
- Will the highest temperature in Chicago be between 80-81°F on August 18?53¢
- Will the highest temperature in Chicago be between 82-83°F on August 18?23¢
- Will the highest temperature in Chicago be between 84-85°F on August 18?6¢
- Will the highest temperature in Chicago be between 86-87°F on August 18?2¢
- Will the highest temperature in Chicago be between 88-89°F on August 18?<1¢
- Will the highest temperature in Chicago be 90°F or higher on August 18?<1¢
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section. This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 18 Aug '26. The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD. To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C. This market can not resolve until the first data point for the following date has been published on the resolution source. The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market. Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Recent National Weather Service guidance and model consensus indicate a moderating high-pressure system will bring highs near or slightly below the August 18 climatological normal of 82.5°F at Chicago O’Hare, supporting the market’s strong preference for the 80–81°F bin. A lingering cool, stable airmass following the August 11 derecho has kept recent daytime maxima in the mid-70s, but gradual warming and reduced cloud cover are forecast to lift temperatures into the low 80s. Ensemble spreads remain modest, with limited upside risk from lake-breeze suppression or additional moisture, which aligns with the combined 74.5% implied probability for 80–83°F outcomes. Updated NWS short-range forecasts and next model runs will provide the key data points ahead of resolution.