**Forecast consensus from the National Weather Service and major models centers on an overnight low in the low-to-mid 60s for Chicago on September 19, driven by persistent cloud cover, widespread showers and thunderstorms, and moderating southeast-to-northeast winds that limit radiational cooling.** These conditions, associated with an incoming weather system, keep minimum temperatures well above the late-September climatological average of roughly 57°F. Latest NWS guidance and ensemble runs show the daily minimum most likely between 61–65°F, aligning with the market’s heaviest positioning on the 62–65°F brackets. Updated model runs overnight or early on the 19th will be the key near-term catalyst for any shifts in implied probabilities.
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 52%
62-63°F 50%
64-65°F 40%
60-61°F 39%
NEW
NEW
Sep 19, 2026
55°F or below
2%
56-57°F
7%
58-59°F
10%
60-61°F
39%
62-63°F
50%
64-65°F
35%
66-67°F
52%
68-69°F
11%
70-71°F
7%
72-73°F
2%
74°F or higher
1%
66-67°F 52%
62-63°F 50%
64-65°F 40%
60-61°F 39%
NEW
NEW
Sep 19, 2026
55°F or below
$41 Vol.
2%
56-57°F
$0 Vol.
7%
58-59°F
$0 Vol.
10%
60-61°F
$51 Vol.
39%
62-63°F
$0 Vol.
50%
64-65°F
$5 Vol.
35%
66-67°F
$0 Vol.
52%
68-69°F
$0 Vol.
11%
70-71°F
$0 Vol.
7%
72-73°F
$41 Vol.
2%
74°F or higher
$41 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.**Forecast consensus from the National Weather Service and major models centers on an overnight low in the low-to-mid 60s for Chicago on September 19, driven by persistent cloud cover, widespread showers and thunderstorms, and moderating southeast-to-northeast winds that limit radiational cooling.**
These conditions, associated with an incoming weather system, keep minimum temperatures well above the late-September climatological average of roughly 57°F. Latest NWS guidance and ensemble runs show the daily minimum most likely between 61–65°F, aligning with the market’s heaviest positioning on the 62–65°F brackets. Updated model runs overnight or early on the 19th will be the key near-term catalyst for any shifts in implied probabilities.
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
$179End 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.**Forecast consensus from the National Weather Service and major models centers on an overnight low in the low-to-mid 60s for Chicago on September 19, driven by persistent cloud cover, widespread showers and thunderstorms, and moderating southeast-to-northeast winds that limit radiational cooling.**
These conditions, associated with an incoming weather system, keep minimum temperatures well above the late-September climatological average of roughly 57°F. Latest NWS guidance and ensemble runs show the daily minimum most likely between 61–65°F, aligning with the market’s heaviest positioning on the 62–65°F brackets. Updated model runs overnight or early on the 19th will be the key near-term catalyst for any shifts in implied probabilities.
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
$179End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...**Forecast consensus from the National Weather Service and major models centers on an overnight low in the low-to-mid 60s for Chicago on September 19, driven by persistent cloud cover, widespread showers and thunderstorms, and moderating southeast-to-northeast winds that limit radiational cooling.** These conditions, associated with an incoming weather system, keep minimum temperatures well above the late-September climatological average of roughly 57°F. Latest NWS guidance and ensemble runs show the daily minimum most likely between 61–65°F, aligning with the market’s heaviest positioning on the 62–65°F brackets. Updated model runs overnight or early on the 19th will be the key near-term catalyst for any shifts in implied probabilities.
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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