Recent National Weather Service and ensemble forecasts for Chicago indicate the daily minimum temperature on September 19 will most likely fall in the low-to-mid 60s, driven by persistent cloud cover, high dew points near 64–66°F, and southeasterly flow that limits nocturnal radiative cooling. Official guidance from NWS Chicago and nearby model runs consistently project overnight lows around 64–65°F, with limited potential for deeper cooling under the humid, overcast regime. This pattern deviates from the 1991–2020 climatological average low of 57°F for the date, reflecting warmer-than-normal boundary-layer conditions. Traders have priced 62–63°F highest at 50% implied probability, followed closely by 64–65°F at 34.5%, as model consensus remains tight but allows for minor shifts from final observational data or localized variations at the official reporting station. Updated NWS briefings and hourly observations through the overnight period represent the key near-term catalysts.
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 19?
Lowest temperature in Chicago on September 19?
66-67°F 51%
62-63°F 50%
64-65°F 40%
60-61°F 39%
NEW
NEW
Sep 19, 2026
55°F or below
1%
56-57°F
5%
58-59°F
8%
60-61°F
39%
62-63°F
50%
64-65°F
35%
66-67°F
51%
68-69°F
11%
70-71°F
7%
72-73°F
1%
74°F or higher
1%
66-67°F 51%
62-63°F 50%
64-65°F 40%
60-61°F 39%
NEW
NEW
Sep 19, 2026
55°F or below
$0 Vol.
1%
56-57°F
$0 Vol.
5%
58-59°F
$0 Vol.
8%
60-61°F
$51 Vol.
39%
62-63°F
$0 Vol.
50%
64-65°F
$5 Vol.
35%
66-67°F
$0 Vol.
51%
68-69°F
$0 Vol.
11%
70-71°F
$0 Vol.
7%
72-73°F
$0 Vol.
1%
74°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 19 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.Recent National Weather Service and ensemble forecasts for Chicago indicate the daily minimum temperature on September 19 will most likely fall in the low-to-mid 60s, driven by persistent cloud cover, high dew points near 64–66°F, and southeasterly flow that limits nocturnal radiative cooling. Official guidance from NWS Chicago and nearby model runs consistently project overnight lows around 64–65°F, with limited potential for deeper cooling under the humid, overcast regime. This pattern deviates from the 1991–2020 climatological average low of 57°F for the date, reflecting warmer-than-normal boundary-layer conditions. Traders have priced 62–63°F highest at 50% implied probability, followed closely by 64–65°F at 34.5%, as model consensus remains tight but allows for minor shifts from final observational data or localized variations at the official reporting station. Updated NWS briefings and hourly observations through the overnight period represent the key near-term catalysts.
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 19 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 17, 2026, 3:29 AM ET
Volume
$56End Date
Sep 19, 2026Market Opened
Sep 17, 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 19 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.Recent National Weather Service and ensemble forecasts for Chicago indicate the daily minimum temperature on September 19 will most likely fall in the low-to-mid 60s, driven by persistent cloud cover, high dew points near 64–66°F, and southeasterly flow that limits nocturnal radiative cooling. Official guidance from NWS Chicago and nearby model runs consistently project overnight lows around 64–65°F, with limited potential for deeper cooling under the humid, overcast regime. This pattern deviates from the 1991–2020 climatological average low of 57°F for the date, reflecting warmer-than-normal boundary-layer conditions. Traders have priced 62–63°F highest at 50% implied probability, followed closely by 64–65°F at 34.5%, as model consensus remains tight but allows for minor shifts from final observational data or localized variations at the official reporting station. Updated NWS briefings and hourly observations through the overnight period represent the key near-term catalysts.
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 19 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
$56End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Recent National Weather Service and ensemble forecasts for Chicago indicate the daily minimum temperature on September 19 will most likely fall in the low-to-mid 60s, driven by persistent cloud cover, high dew points near 64–66°F, and southeasterly flow that limits nocturnal radiative cooling. Official guidance from NWS Chicago and nearby model runs consistently project overnight lows around 64–65°F, with limited potential for deeper cooling under the humid, overcast regime. This pattern deviates from the 1991–2020 climatological average low of 57°F for the date, reflecting warmer-than-normal boundary-layer conditions. Traders have priced 62–63°F highest at 50% implied probability, followed closely by 64–65°F at 34.5%, as model consensus remains tight but allows for minor shifts from final observational data or localized variations at the official reporting station. Updated NWS briefings and hourly observations through the overnight period represent the key near-term catalysts.
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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