Official National Weather Service guidance and ensemble model runs for August 13 point to a Chicago high in the mid- to upper-70s°F, driven by moderating air mass behind earlier heat, modest southerly flow, and variable cloud cover or scattered showers that limit peak insolation. The tight clustering around 74–79°F reflects modest forecast spread in timing of any convection and boundary-layer mixing, with historical August variability around 79°F providing context. Traders weigh the latest model updates and local mesonet trends ahead of the daily maximum observation at official stations.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Chicago on August 13?
76-77°F 31%
74-75°F 24%
78-79°F 23%
80-81°F 9%
67°F or below
<1%
68-69°F
1%
70-71°F
6%
72-73°F
5%
74-75°F
24%
76-77°F
31%
78-79°F
23%
80-81°F
9%
82-83°F
3%
84-85°F
2%
86°F or higher
1%
76-77°F 31%
74-75°F 24%
78-79°F 23%
80-81°F 9%
67°F or below
<1%
68-69°F
1%
70-71°F
6%
72-73°F
5%
74-75°F
24%
76-77°F
31%
78-79°F
23%
80-81°F
9%
82-83°F
3%
84-85°F
2%
86°F or higher
1%
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 13 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.
Market Opened: Aug 11, 2026, 9:02 PM ET
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...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 13 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.
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Official National Weather Service guidance and ensemble model runs for August 13 point to a Chicago high in the mid- to upper-70s°F, driven by moderating air mass behind earlier heat, modest southerly flow, and variable cloud cover or scattered showers that limit peak insolation. The tight clustering around 74–79°F reflects modest forecast spread in timing of any convection and boundary-layer mixing, with historical August variability around 79°F providing context. Traders weigh the latest model updates and local mesonet trends ahead of the daily maximum observation at official stations.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated

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