Recent National Weather Service guidance and ensemble model runs indicate a high near 73°F for Chicago on September 19 amid widespread showers and thunderstorms, with southeast winds shifting northeast and extensive cloud cover suppressing peak heating. This frontal system has introduced notable forecast spread in timing and intensity of precipitation, keeping the market-implied probabilities tightly clustered between the 69°F-or-below, 70-71°F, and 72-73°F bins. Persistent moisture and reduced insolation differentiate these narrow ranges more than seasonal norms, which average about 75°F. Updated short-range model output and NWS briefings expected later today will likely narrow the distribution ahead of 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 28%
70-71°F 27%
69°F or below 22%
74-75°F 18%
NEW
$10,990 Vol.
NEW
$10,990 Vol.
Sep 19, 2026
69°F or below
22%
70-71°F
27%
72-73°F
28%
74-75°F
18%
76-77°F
8%
78-79°F
3%
80-81°F
<1%
82-83°F
<1%
84-85°F
<1%
86-87°F
<1%
88°F or higher
<1%
72-73°F 28%
70-71°F 27%
69°F or below 22%
74-75°F 18%
NEW
$10,990 Vol.
NEW
$10,990 Vol.
Sep 19, 2026
69°F or below
$3,843 Vol.
22%
70-71°F
$2,405 Vol.
27%
72-73°F
$1,336 Vol.
28%
74-75°F
$1,132 Vol.
18%
76-77°F
$634 Vol.
8%
78-79°F
$705 Vol.
3%
80-81°F
$491 Vol.
<1%
82-83°F
$111 Vol.
<1%
84-85°F
$111 Vol.
<1%
86-87°F
$111 Vol.
<1%
88°F or higher
$111 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 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 guidance and ensemble model runs indicate a high near 73°F for Chicago on September 19 amid widespread showers and thunderstorms, with southeast winds shifting northeast and extensive cloud cover suppressing peak heating. This frontal system has introduced notable forecast spread in timing and intensity of precipitation, keeping the market-implied probabilities tightly clustered between the 69°F-or-below, 70-71°F, and 72-73°F bins. Persistent moisture and reduced insolation differentiate these narrow ranges more than seasonal norms, which average about 75°F. Updated short-range model output and NWS briefings expected later today will likely narrow the distribution ahead of 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
$10,990End 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 guidance and ensemble model runs indicate a high near 73°F for Chicago on September 19 amid widespread showers and thunderstorms, with southeast winds shifting northeast and extensive cloud cover suppressing peak heating. This frontal system has introduced notable forecast spread in timing and intensity of precipitation, keeping the market-implied probabilities tightly clustered between the 69°F-or-below, 70-71°F, and 72-73°F bins. Persistent moisture and reduced insolation differentiate these narrow ranges more than seasonal norms, which average about 75°F. Updated short-range model output and NWS briefings expected later today will likely narrow the distribution ahead of 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
$10,990End 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 guidance and ensemble model runs indicate a high near 73°F for Chicago on September 19 amid widespread showers and thunderstorms, with southeast winds shifting northeast and extensive cloud cover suppressing peak heating. This frontal system has introduced notable forecast spread in timing and intensity of precipitation, keeping the market-implied probabilities tightly clustered between the 69°F-or-below, 70-71°F, and 72-73°F bins. Persistent moisture and reduced insolation differentiate these narrow ranges more than seasonal norms, which average about 75°F. Updated short-range model output and NWS briefings expected later today will likely narrow the distribution ahead of 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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