**Forecast consensus from National Weather Service and other models points to a high near 80°F in Chicago on September 9, 2026, with showers and clouds likely moderating peak readings.** Recent cooling after early-September heat (highs of 91–96°F September 1–4) has shifted conditions toward more typical late-summer patterns, with southwest winds, high humidity, and a 60% precipitation chance expected to limit afternoon warming. Official outlooks show morning showers followed by partly to mostly cloudy skies, keeping the daily maximum in the lower 80s rather than allowing full solar heating. Model differences center on the exact timing and coverage of rain and cloud breaks, which can shift the high by 1–3°F and explain the tight clustering of market-implied odds around 78–83°F. Historical norms place the September 9 average high at roughly 78.6°F, providing context for why traders heavily weight the 80–81°F bin (31%) while assigning meaningful probability to adjacent ranges. New NWS updates and refined model runs over the next 48 hours will likely refine these probabilities as the event nears 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 September 9?
Highest temperature in Chicago on September 9?
80-81°F 31%
82-83°F 23%
78-79°F 22%
76-77°F 10%
NEW
NEW
Sep 9, 2026
75°F or below
5%
76-77°F
10%
78-79°F
22%
80-81°F
31%
82-83°F
23%
84-85°F
9%
86-87°F
7%
88-89°F
3%
90-91°F
3%
92-93°F
3%
94°F or higher
1%
80-81°F 31%
82-83°F 23%
78-79°F 22%
76-77°F 10%
NEW
NEW
Sep 9, 2026
75°F or below
$49 Vol.
5%
76-77°F
$6 Vol.
10%
78-79°F
$57 Vol.
22%
80-81°F
$71 Vol.
31%
82-83°F
$42 Vol.
23%
84-85°F
$37 Vol.
9%
86-87°F
$0 Vol.
7%
88-89°F
$0 Vol.
3%
90-91°F
$0 Vol.
3%
92-93°F
$0 Vol.
3%
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 9 Sep '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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.**Forecast consensus from National Weather Service and other models points to a high near 80°F in Chicago on September 9, 2026, with showers and clouds likely moderating peak readings.** Recent cooling after early-September heat (highs of 91–96°F September 1–4) has shifted conditions toward more typical late-summer patterns, with southwest winds, high humidity, and a 60% precipitation chance expected to limit afternoon warming. Official outlooks show morning showers followed by partly to mostly cloudy skies, keeping the daily maximum in the lower 80s rather than allowing full solar heating.
Model differences center on the exact timing and coverage of rain and cloud breaks, which can shift the high by 1–3°F and explain the tight clustering of market-implied odds around 78–83°F. Historical norms place the September 9 average high at roughly 78.6°F, providing context for why traders heavily weight the 80–81°F bin (31%) while assigning meaningful probability to adjacent ranges. New NWS updates and refined model runs over the next 48 hours will likely refine these probabilities as the event nears 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 9 Sep '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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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: Sep 7, 2026, 3:56 AM ET
Volume
$262End Date
Sep 9, 2026Market Opened
Sep 7, 2026, 3:56 AM 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 9 Sep '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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.**Forecast consensus from National Weather Service and other models points to a high near 80°F in Chicago on September 9, 2026, with showers and clouds likely moderating peak readings.** Recent cooling after early-September heat (highs of 91–96°F September 1–4) has shifted conditions toward more typical late-summer patterns, with southwest winds, high humidity, and a 60% precipitation chance expected to limit afternoon warming. Official outlooks show morning showers followed by partly to mostly cloudy skies, keeping the daily maximum in the lower 80s rather than allowing full solar heating.
Model differences center on the exact timing and coverage of rain and cloud breaks, which can shift the high by 1–3°F and explain the tight clustering of market-implied odds around 78–83°F. Historical norms place the September 9 average high at roughly 78.6°F, providing context for why traders heavily weight the 80–81°F bin (31%) while assigning meaningful probability to adjacent ranges. New NWS updates and refined model runs over the next 48 hours will likely refine these probabilities as the event nears 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 9 Sep '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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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 for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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
$262End Date
Sep 9, 2026Market Opened
Sep 7, 2026, 3:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...**Forecast consensus from National Weather Service and other models points to a high near 80°F in Chicago on September 9, 2026, with showers and clouds likely moderating peak readings.** Recent cooling after early-September heat (highs of 91–96°F September 1–4) has shifted conditions toward more typical late-summer patterns, with southwest winds, high humidity, and a 60% precipitation chance expected to limit afternoon warming. Official outlooks show morning showers followed by partly to mostly cloudy skies, keeping the daily maximum in the lower 80s rather than allowing full solar heating. Model differences center on the exact timing and coverage of rain and cloud breaks, which can shift the high by 1–3°F and explain the tight clustering of market-implied odds around 78–83°F. Historical norms place the September 9 average high at roughly 78.6°F, providing context for why traders heavily weight the 80–81°F bin (31%) while assigning meaningful probability to adjacent ranges. New NWS updates and refined model runs over the next 48 hours will likely refine these probabilities as the event nears 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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