**The leading 60-61°F bin at 61% reflects the official National Weather Service observation at Chicago O’Hare, where the minimum temperature reached 60°F at 7:53 AM on September 21, 2026, under a cool, cloudy regime with light rain, fog, and persistent northeasterly flow.** This was 5°F above the 1991–2020 normal low of 55°F yet well below the seasonal average high of 74°F, as a strong high-pressure system and onshore flow suppressed warming. The daily maximum of only 66°F (8°F below normal) further constrained overnight lows. Market-implied odds for adjacent cooler ranges (58-59°F at 46.5%, 54-55°F at 45%) remain elevated due to model spread and typical microclimate variations between stations, while warmer bins sit near zero. With the climatological report now issued, trader consensus has aligned closely with the verified 60°F reading.
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?
58-59°F 47%
56-57°F 43%
50-51°F 1.9%
49°F or below 1.7%
$1,243 Vol.
$1,243 Vol.
Sep 21, 2026
49°F or below
2%
50-51°F
2%
52-53°F
-
54-55°F
-
56-57°F
43%
58-59°F
47%
60-61°F
61%
62-63°F
<1%
64-65°F
<1%
66-67°F
<1%
68°F or higher
<1%
58-59°F 47%
56-57°F 43%
50-51°F 1.9%
49°F or below 1.7%
$1,243 Vol.
$1,243 Vol.
Sep 21, 2026
49°F or below
$31 Vol.
2%
50-51°F
$36 Vol.
2%
52-53°F
$27 Vol.
-
54-55°F
$37 Vol.
-
56-57°F
$0 Vol.
43%
58-59°F
$0 Vol.
47%
60-61°F
$16 Vol.
61%
62-63°F
$1,001 Vol.
<1%
64-65°F
$15 Vol.
<1%
66-67°F
$15 Vol.
<1%
68°F or higher
$65 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.**The leading 60-61°F bin at 61% reflects the official National Weather Service observation at Chicago O’Hare, where the minimum temperature reached 60°F at 7:53 AM on September 21, 2026, under a cool, cloudy regime with light rain, fog, and persistent northeasterly flow.**
This was 5°F above the 1991–2020 normal low of 55°F yet well below the seasonal average high of 74°F, as a strong high-pressure system and onshore flow suppressed warming. The daily maximum of only 66°F (8°F below normal) further constrained overnight lows. Market-implied odds for adjacent cooler ranges (58-59°F at 46.5%, 54-55°F at 45%) remain elevated due to model spread and typical microclimate variations between stations, while warmer bins sit near zero. With the climatological report now issued, trader consensus has aligned closely with the verified 60°F reading.
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
$1,243End 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.**The leading 60-61°F bin at 61% reflects the official National Weather Service observation at Chicago O’Hare, where the minimum temperature reached 60°F at 7:53 AM on September 21, 2026, under a cool, cloudy regime with light rain, fog, and persistent northeasterly flow.**
This was 5°F above the 1991–2020 normal low of 55°F yet well below the seasonal average high of 74°F, as a strong high-pressure system and onshore flow suppressed warming. The daily maximum of only 66°F (8°F below normal) further constrained overnight lows. Market-implied odds for adjacent cooler ranges (58-59°F at 46.5%, 54-55°F at 45%) remain elevated due to model spread and typical microclimate variations between stations, while warmer bins sit near zero. With the climatological report now issued, trader consensus has aligned closely with the verified 60°F reading.
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
$1,243End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...**The leading 60-61°F bin at 61% reflects the official National Weather Service observation at Chicago O’Hare, where the minimum temperature reached 60°F at 7:53 AM on September 21, 2026, under a cool, cloudy regime with light rain, fog, and persistent northeasterly flow.** This was 5°F above the 1991–2020 normal low of 55°F yet well below the seasonal average high of 74°F, as a strong high-pressure system and onshore flow suppressed warming. The daily maximum of only 66°F (8°F below normal) further constrained overnight lows. Market-implied odds for adjacent cooler ranges (58-59°F at 46.5%, 54-55°F at 45%) remain elevated due to model spread and typical microclimate variations between stations, while warmer bins sit near zero. With the climatological report now issued, trader consensus has aligned closely with the verified 60°F reading.
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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