Recent National Weather Service and GFS-based forecasts for Chicago indicate a minimum temperature near 56–58°F on September 26 under mostly cloudy skies and persistent easterly flow, yet the market’s near-even split between 45°F or below (50.0%) and 64°F or higher (49.5%) highlights substantial short-range model uncertainty. Key differentiators include the strength and timing of radiational cooling overnight, variable cloud cover that could either suppress or enhance temperature drops, and subtle shifts in low-level wind direction off Lake Michigan that modulate marine air influence. With resolution hinging on the precise overnight low within a narrow 48-hour window, traders are weighting the latest model runs and observational trends from Chicago O’Hare, where historical September minima average around 54°F.
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 26?
Lowest temperature in Chicago on September 26?
64°F or higher 99%
52-53°F 40%
54-55°F 40%
46-47°F 38%
NEW
NEW
Sep 26, 2026
45°F or below
<1%
46-47°F
38%
48-49°F
38%
50-51°F
38%
52-53°F
40%
54-55°F
40%
56-57°F
38%
58-59°F
38%
60-61°F
38%
62-63°F
38%
64°F or higher
99%
64°F or higher 99%
52-53°F 40%
54-55°F 40%
46-47°F 38%
NEW
NEW
Sep 26, 2026
45°F or below
$0 Vol.
<1%
46-47°F
$0 Vol.
38%
48-49°F
$0 Vol.
38%
50-51°F
$0 Vol.
38%
52-53°F
$0 Vol.
40%
54-55°F
$0 Vol.
40%
56-57°F
$0 Vol.
38%
58-59°F
$0 Vol.
38%
60-61°F
$0 Vol.
38%
62-63°F
$0 Vol.
38%
64°F or higher
$0 Vol.
99%
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 26 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 GFS-based forecasts for Chicago indicate a minimum temperature near 56–58°F on September 26 under mostly cloudy skies and persistent easterly flow, yet the market’s near-even split between 45°F or below (50.0%) and 64°F or higher (49.5%) highlights substantial short-range model uncertainty. Key differentiators include the strength and timing of radiational cooling overnight, variable cloud cover that could either suppress or enhance temperature drops, and subtle shifts in low-level wind direction off Lake Michigan that modulate marine air influence. With resolution hinging on the precise overnight low within a narrow 48-hour window, traders are weighting the latest model runs and observational trends from Chicago O’Hare, where historical September minima average around 54°F.
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 26 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 24, 2026, 3:29 AM ET
Volume
$0End Date
Sep 26, 2026Market Opened
Sep 24, 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 26 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 GFS-based forecasts for Chicago indicate a minimum temperature near 56–58°F on September 26 under mostly cloudy skies and persistent easterly flow, yet the market’s near-even split between 45°F or below (50.0%) and 64°F or higher (49.5%) highlights substantial short-range model uncertainty. Key differentiators include the strength and timing of radiational cooling overnight, variable cloud cover that could either suppress or enhance temperature drops, and subtle shifts in low-level wind direction off Lake Michigan that modulate marine air influence. With resolution hinging on the precise overnight low within a narrow 48-hour window, traders are weighting the latest model runs and observational trends from Chicago O’Hare, where historical September minima average around 54°F.
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 26 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 26, 2026Market Opened
Sep 24, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47de9d...Recent National Weather Service and GFS-based forecasts for Chicago indicate a minimum temperature near 56–58°F on September 26 under mostly cloudy skies and persistent easterly flow, yet the market’s near-even split between 45°F or below (50.0%) and 64°F or higher (49.5%) highlights substantial short-range model uncertainty. Key differentiators include the strength and timing of radiational cooling overnight, variable cloud cover that could either suppress or enhance temperature drops, and subtle shifts in low-level wind direction off Lake Michigan that modulate marine air influence. With resolution hinging on the precise overnight low within a narrow 48-hour window, traders are weighting the latest model runs and observational trends from Chicago O’Hare, where historical September minima average around 54°F.
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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