**NWS forecasts for Chicago on September 21 project an overnight low near 56°F under persistent northeast winds of 15-20 mph with gusts to 25 mph, widespread cloud cover, and a chance of showers, which limits radiational cooling.** Model consensus and recent observations support mid-50s readings as the most likely minimum, consistent with the historical average low of 56.4°F for the date. Trader emphasis on the 58-61°F range reflects uncertainty in exact timing of any wind shift or partial clearing that could raise the floor by a few degrees, while lower-probability outcomes below 56°F or above 62°F would require larger forecast revisions. Updated NWS guidance and model runs through the overnight period remain the key near-term catalysts for market movement.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Chicago on September 21?
Lowest temperature in Chicago on September 21?
62-63°F 39%
58-59°F 36%
60-61°F 36%
56-57°F 21%
NEW
NEW
Sep 21, 2026
49°F or below
1%
50-51°F
2%
52-53°F
6%
54-55°F
11%
56-57°F
21%
58-59°F
36%
60-61°F
36%
62-63°F
39%
64-65°F
9%
66-67°F
6%
68°F or higher
1%
62-63°F 39%
58-59°F 36%
60-61°F 36%
56-57°F 21%
NEW
NEW
Sep 21, 2026
49°F or below
$0 Vol.
1%
50-51°F
$0 Vol.
2%
52-53°F
$0 Vol.
6%
54-55°F
$0 Vol.
11%
56-57°F
$0 Vol.
21%
58-59°F
$0 Vol.
36%
60-61°F
$0 Vol.
36%
62-63°F
$0 Vol.
39%
64-65°F
$0 Vol.
9%
66-67°F
$0 Vol.
6%
68°F or higher
$0 Vol.
1%
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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.**NWS forecasts for Chicago on September 21 project an overnight low near 56°F under persistent northeast winds of 15-20 mph with gusts to 25 mph, widespread cloud cover, and a chance of showers, which limits radiational cooling.** Model consensus and recent observations support mid-50s readings as the most likely minimum, consistent with the historical average low of 56.4°F for the date. Trader emphasis on the 58-61°F range reflects uncertainty in exact timing of any wind shift or partial clearing that could raise the floor by a few degrees, while lower-probability outcomes below 56°F or above 62°F would require larger forecast revisions. Updated NWS guidance and model runs through the overnight period remain the key near-term catalysts for market movement.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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 19, 2026, 3:29 AM ET
Volume
$0End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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.**NWS forecasts for Chicago on September 21 project an overnight low near 56°F under persistent northeast winds of 15-20 mph with gusts to 25 mph, widespread cloud cover, and a chance of showers, which limits radiational cooling.** Model consensus and recent observations support mid-50s readings as the most likely minimum, consistent with the historical average low of 56.4°F for the date. Trader emphasis on the 58-61°F range reflects uncertainty in exact timing of any wind shift or partial clearing that could raise the floor by a few degrees, while lower-probability outcomes below 56°F or above 62°F would require larger forecast revisions. Updated NWS guidance and model runs through the overnight period remain the key near-term catalysts for market movement.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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
$0End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...**NWS forecasts for Chicago on September 21 project an overnight low near 56°F under persistent northeast winds of 15-20 mph with gusts to 25 mph, widespread cloud cover, and a chance of showers, which limits radiational cooling.** Model consensus and recent observations support mid-50s readings as the most likely minimum, consistent with the historical average low of 56.4°F for the date. Trader emphasis on the 58-61°F range reflects uncertainty in exact timing of any wind shift or partial clearing that could raise the floor by a few degrees, while lower-probability outcomes below 56°F or above 62°F would require larger forecast revisions. Updated NWS guidance and model runs through the overnight period remain the key near-term catalysts for market movement.
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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