Recent National Weather Service forecasts for Chicago O’Hare point to a Saturday high near 80°F amid showers and thunderstorms, yet model consensus and lake-effect moderation have kept market-implied odds centered on 72–75°F. Persistent cloud cover, high humidity, and precipitation timing reduce the chance of full solar heating, while steering patterns and boundary-layer moisture introduce spread across the 70–80°F range. Historical September 19 averages near 75°F provide context, but short-term variability in convective timing and wind direction remains the dominant uncertainty. Updated NWS guidance and afternoon model runs through Friday will likely refine these probabilities ahead of market 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 19?
Highest temperature in Chicago on September 19?
72-73°F 40%
70-71°F 39%
74-75°F 39%
76-77°F 39%
NEW
NEW
Sep 19, 2026
69°F or below
5%
70-71°F
30%
72-73°F
28%
74-75°F
39%
76-77°F
39%
78-79°F
19%
80-81°F
17%
82-83°F
14%
84-85°F
10%
86-87°F
5%
88°F or higher
5%
72-73°F 40%
70-71°F 39%
74-75°F 39%
76-77°F 39%
NEW
NEW
Sep 19, 2026
69°F or below
$5 Vol.
5%
70-71°F
$0 Vol.
30%
72-73°F
$30 Vol.
28%
74-75°F
$0 Vol.
39%
76-77°F
$0 Vol.
39%
78-79°F
$0 Vol.
19%
80-81°F
$0 Vol.
17%
82-83°F
$0 Vol.
14%
84-85°F
$0 Vol.
10%
86-87°F
$0 Vol.
5%
88°F or higher
$0 Vol.
5%
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 19 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.Recent National Weather Service forecasts for Chicago O’Hare point to a Saturday high near 80°F amid showers and thunderstorms, yet model consensus and lake-effect moderation have kept market-implied odds centered on 72–75°F. Persistent cloud cover, high humidity, and precipitation timing reduce the chance of full solar heating, while steering patterns and boundary-layer moisture introduce spread across the 70–80°F range. Historical September 19 averages near 75°F provide context, but short-term variability in convective timing and wind direction remains the dominant uncertainty. Updated NWS guidance and afternoon model runs through Friday will likely refine these probabilities ahead of market 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 19 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 17, 2026, 2:56 AM ET
Volume
$35End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 2:56 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 19 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.Recent National Weather Service forecasts for Chicago O’Hare point to a Saturday high near 80°F amid showers and thunderstorms, yet model consensus and lake-effect moderation have kept market-implied odds centered on 72–75°F. Persistent cloud cover, high humidity, and precipitation timing reduce the chance of full solar heating, while steering patterns and boundary-layer moisture introduce spread across the 70–80°F range. Historical September 19 averages near 75°F provide context, but short-term variability in convective timing and wind direction remains the dominant uncertainty. Updated NWS guidance and afternoon model runs through Friday will likely refine these probabilities ahead of market 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 19 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
$35End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 2:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Recent National Weather Service forecasts for Chicago O’Hare point to a Saturday high near 80°F amid showers and thunderstorms, yet model consensus and lake-effect moderation have kept market-implied odds centered on 72–75°F. Persistent cloud cover, high humidity, and precipitation timing reduce the chance of full solar heating, while steering patterns and boundary-layer moisture introduce spread across the 70–80°F range. Historical September 19 averages near 75°F provide context, but short-term variability in convective timing and wind direction remains the dominant uncertainty. Updated NWS guidance and afternoon model runs through Friday will likely refine these probabilities ahead of market 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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