Cool Canadian air and persistent northerly flow off Lake Michigan are suppressing Chicago temperatures well below late-August norms on August 23, 2026, positioning official highs in the mid-70s and driving the 76-77°F bin to 61.5% implied probability. National Weather Service forecasts and real-time observations consistently point to a peak near 73-77°F under partly cloudy skies, with lake moderation and light winds limiting afternoon warming. This aligns with the market’s tight clustering around 74-77°F, as traders weigh NWS and NOAA model consensus against historical averages near 82°F and the low risk of any late surge.
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 23?
Highest temperature in Chicago on August 23?
76-77°F 62%
74-75°F 20%
78-79°F 6%
80-81°F <1%
$25,815 Vol.
$25,815 Vol.
Aug 23, 2026
65°F or below
<1%
66-67°F
<1%
68-69°F
<1%
70-71°F
<1%
72-73°F
<1%
74-75°F
30%
76-77°F
62%
78-79°F
6%
80-81°F
1%
82-83°F
1%
84°F or higher
<1%
76-77°F 62%
74-75°F 20%
78-79°F 6%
80-81°F <1%
$25,815 Vol.
$25,815 Vol.
Aug 23, 2026
65°F or below
$826 Vol.
<1%
66-67°F
$828 Vol.
<1%
68-69°F
$2,999 Vol.
<1%
70-71°F
$2,429 Vol.
<1%
72-73°F
$1,869 Vol.
<1%
74-75°F
$3,763 Vol.
30%
76-77°F
$4,343 Vol.
62%
78-79°F
$4,023 Vol.
6%
80-81°F
$1,874 Vol.
1%
82-83°F
$1,366 Vol.
1%
84°F or higher
$1,493 Vol.
<1%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 23 Aug '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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.Cool Canadian air and persistent northerly flow off Lake Michigan are suppressing Chicago temperatures well below late-August norms on August 23, 2026, positioning official highs in the mid-70s and driving the 76-77°F bin to 61.5% implied probability. National Weather Service forecasts and real-time observations consistently point to a peak near 73-77°F under partly cloudy skies, with lake moderation and light winds limiting afternoon warming. This aligns with the market’s tight clustering around 74-77°F, as traders weigh NWS and NOAA model consensus against historical averages near 82°F and the low risk of any late surge.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 23 Aug '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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 21, 2026, 11:56 PM ET
Volume
$25,815End Date
Aug 23, 2026Market Opened
Aug 21, 2026, 11:56 PM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 23 Aug '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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.Cool Canadian air and persistent northerly flow off Lake Michigan are suppressing Chicago temperatures well below late-August norms on August 23, 2026, positioning official highs in the mid-70s and driving the 76-77°F bin to 61.5% implied probability. National Weather Service forecasts and real-time observations consistently point to a peak near 73-77°F under partly cloudy skies, with lake moderation and light winds limiting afternoon warming. This aligns with the market’s tight clustering around 74-77°F, as traders weigh NWS and NOAA model consensus against historical averages near 82°F and the low risk of any late surge.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 23 Aug '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=kord
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
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.
Volume
$25,815End Date
Aug 23, 2026Market Opened
Aug 21, 2026, 11:56 PM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Cool Canadian air and persistent northerly flow off Lake Michigan are suppressing Chicago temperatures well below late-August norms on August 23, 2026, positioning official highs in the mid-70s and driving the 76-77°F bin to 61.5% implied probability. National Weather Service forecasts and real-time observations consistently point to a peak near 73-77°F under partly cloudy skies, with lake moderation and light winds limiting afternoon warming. This aligns with the market’s tight clustering around 74-77°F, as traders weigh NWS and NOAA model consensus against historical averages near 82°F and the low risk of any late surge.
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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