Recent National Weather Service model runs reveal substantial uncertainty in Chicago's August 26 high temperature, with ensemble guidance split between a cooler scenario near 76–77°F driven by early cloud cover and a possible frontal passage, versus hotter outcomes of 90–91°F or 94°F+ if clear skies and southerly flow allow stronger daytime heating. This 50% clustering on divergent bins reflects typical late-August variability in the Midwest, where small shifts in timing of moisture advection or boundary-layer mixing can alter maximums by 10–15°F. Historical climatology shows August highs averaging 82°F, underscoring why traders weigh updated HRRR and GFS solutions heavily ahead of tomorrow's resolution.
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 26?
Highest temperature in Chicago on August 26?
84-85°F 36%
82-83°F 34%
80-81°F 13%
88-89°F 9%
NEW
NEW
Aug 26, 2026
75°F or below
1%
76-77°F
5%
78-79°F
3%
80-81°F
13%
82-83°F
34%
84-85°F
36%
86-87°F
8%
88-89°F
9%
90-91°F
1%
92-93°F
<1%
94°F or higher
<1%
84-85°F 36%
82-83°F 34%
80-81°F 13%
88-89°F 9%
NEW
NEW
Aug 26, 2026
75°F or below
$0 Vol.
1%
76-77°F
$5 Vol.
5%
78-79°F
$0 Vol.
3%
80-81°F
$0 Vol.
13%
82-83°F
$5 Vol.
34%
84-85°F
$5 Vol.
36%
86-87°F
$0 Vol.
8%
88-89°F
$47 Vol.
9%
90-91°F
$5 Vol.
1%
92-93°F
$0 Vol.
<1%
94°F or higher
$0 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 26 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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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.Recent National Weather Service model runs reveal substantial uncertainty in Chicago's August 26 high temperature, with ensemble guidance split between a cooler scenario near 76–77°F driven by early cloud cover and a possible frontal passage, versus hotter outcomes of 90–91°F or 94°F+ if clear skies and southerly flow allow stronger daytime heating. This 50% clustering on divergent bins reflects typical late-August variability in the Midwest, where small shifts in timing of moisture advection or boundary-layer mixing can alter maximums by 10–15°F. Historical climatology shows August highs averaging 82°F, underscoring why traders weigh updated HRRR and GFS solutions heavily ahead of tomorrow's resolution.
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 26 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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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 24, 2026, 8:56 PM ET
Volume
$67End Date
Aug 26, 2026Market Opened
Aug 24, 2026, 8:56 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 26 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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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.Recent National Weather Service model runs reveal substantial uncertainty in Chicago's August 26 high temperature, with ensemble guidance split between a cooler scenario near 76–77°F driven by early cloud cover and a possible frontal passage, versus hotter outcomes of 90–91°F or 94°F+ if clear skies and southerly flow allow stronger daytime heating. This 50% clustering on divergent bins reflects typical late-August variability in the Midwest, where small shifts in timing of moisture advection or boundary-layer mixing can alter maximums by 10–15°F. Historical climatology shows August highs averaging 82°F, underscoring why traders weigh updated HRRR and GFS solutions heavily ahead of tomorrow's resolution.
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 26 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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data is unavailable or missing for the observation period, Weather Underground will be used as the secondary resolution source.
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
$67End Date
Aug 26, 2026Market Opened
Aug 24, 2026, 8:56 PM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Recent National Weather Service model runs reveal substantial uncertainty in Chicago's August 26 high temperature, with ensemble guidance split between a cooler scenario near 76–77°F driven by early cloud cover and a possible frontal passage, versus hotter outcomes of 90–91°F or 94°F+ if clear skies and southerly flow allow stronger daytime heating. This 50% clustering on divergent bins reflects typical late-August variability in the Midwest, where small shifts in timing of moisture advection or boundary-layer mixing can alter maximums by 10–15°F. Historical climatology shows August highs averaging 82°F, underscoring why traders weigh updated HRRR and GFS solutions heavily ahead of tomorrow's resolution.
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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