Northwesterly flow advecting cooler Canadian air, combined with Lake Michigan's moderating influence, is the primary driver keeping Chicago's August 23 high in the mid-70s and aligning with the market's near-even split between 74-75°F and 76-77°F outcomes. Model consensus from NWS and AccuWeather indicates peak readings of 73-75°F under mostly sunny skies, several degrees below the 81.8°F climatological normal, as persistent northwest winds limit afternoon heating and suppress lake-breeze warming. Differentiation between the two leading bins hinges on minor variables including sustained wind strength, any residual cloud cover, and precise observational timing at official stations, with traders weighting real-time guidance that shows limited upside potential above 77°F. No major shifts have altered this setup in the past 48 hours.
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?
74-75°F 44%
76-77°F 41%
78-79°F 9%
72-73°F 6%
NEW
$14,404 Vol.
NEW
$14,404 Vol.
Aug 23, 2026
65°F or below
<1%
66-67°F
<1%
68-69°F
<1%
70-71°F
<1%
72-73°F
6%
74-75°F
44%
76-77°F
41%
78-79°F
9%
80-81°F
2%
82-83°F
<1%
84°F or higher
<1%
74-75°F 44%
76-77°F 41%
78-79°F 9%
72-73°F 6%
NEW
$14,404 Vol.
NEW
$14,404 Vol.
Aug 23, 2026
65°F or below
$826 Vol.
<1%
66-67°F
$828 Vol.
<1%
68-69°F
$2,108 Vol.
<1%
70-71°F
$1,314 Vol.
<1%
72-73°F
$885 Vol.
6%
74-75°F
$1,781 Vol.
44%
76-77°F
$1,784 Vol.
41%
78-79°F
$1,854 Vol.
9%
80-81°F
$946 Vol.
2%
82-83°F
$673 Vol.
<1%
84°F or higher
$1,407 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.Northwesterly flow advecting cooler Canadian air, combined with Lake Michigan's moderating influence, is the primary driver keeping Chicago's August 23 high in the mid-70s and aligning with the market's near-even split between 74-75°F and 76-77°F outcomes. Model consensus from NWS and AccuWeather indicates peak readings of 73-75°F under mostly sunny skies, several degrees below the 81.8°F climatological normal, as persistent northwest winds limit afternoon heating and suppress lake-breeze warming. Differentiation between the two leading bins hinges on minor variables including sustained wind strength, any residual cloud cover, and precise observational timing at official stations, with traders weighting real-time guidance that shows limited upside potential above 77°F. No major shifts have altered this setup in the past 48 hours.
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
$14,404End 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.Northwesterly flow advecting cooler Canadian air, combined with Lake Michigan's moderating influence, is the primary driver keeping Chicago's August 23 high in the mid-70s and aligning with the market's near-even split between 74-75°F and 76-77°F outcomes. Model consensus from NWS and AccuWeather indicates peak readings of 73-75°F under mostly sunny skies, several degrees below the 81.8°F climatological normal, as persistent northwest winds limit afternoon heating and suppress lake-breeze warming. Differentiation between the two leading bins hinges on minor variables including sustained wind strength, any residual cloud cover, and precise observational timing at official stations, with traders weighting real-time guidance that shows limited upside potential above 77°F. No major shifts have altered this setup in the past 48 hours.
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
$14,404End Date
Aug 23, 2026Market Opened
Aug 21, 2026, 11:56 PM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Northwesterly flow advecting cooler Canadian air, combined with Lake Michigan's moderating influence, is the primary driver keeping Chicago's August 23 high in the mid-70s and aligning with the market's near-even split between 74-75°F and 76-77°F outcomes. Model consensus from NWS and AccuWeather indicates peak readings of 73-75°F under mostly sunny skies, several degrees below the 81.8°F climatological normal, as persistent northwest winds limit afternoon heating and suppress lake-breeze warming. Differentiation between the two leading bins hinges on minor variables including sustained wind strength, any residual cloud cover, and precise observational timing at official stations, with traders weighting real-time guidance that shows limited upside potential above 77°F. No major shifts have altered this setup in the past 48 hours.
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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