Forecast uncertainty for Chicago's overnight low on September 9 centers on model spread in the position and strength of a weak high-pressure ridge and associated radiational cooling rates. National Weather Service guidance and ensemble runs show the low hovering near 68–74°F, with slight variations in cloud cover, boundary-layer mixing, and Lake Michigan's moderating influence able to shift the outcome across the tightly bunched 67-or-below and 72–73°F bins that currently lead market-implied odds. Recent upper-air analyses indicate limited moisture and light winds, conditions that favor clearer skies and stronger cooling but remain sensitive to small timing shifts in any passing weak front. Historical September climatology places typical lows in the mid-60s, providing a baseline against which traders weigh the latest model consensus and any afternoon updates from NOAA.
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 9?
Lowest temperature in Chicago on September 9?
86°F or higher 71%
70-71°F 44%
67°F or below 34%
72-73°F 34%
NEW
NEW
Sep 9, 2026
67°F or below
34%
68-69°F
25%
70-71°F
28%
72-73°F
34%
74-75°F
28%
76-77°F
17%
78-79°F
1%
80-81°F
1%
82-83°F
1%
84-85°F
<1%
86°F or higher
71%
86°F or higher 71%
70-71°F 44%
67°F or below 34%
72-73°F 34%
NEW
NEW
Sep 9, 2026
67°F or below
$0 Vol.
34%
68-69°F
$0 Vol.
25%
70-71°F
$21 Vol.
28%
72-73°F
$0 Vol.
34%
74-75°F
$0 Vol.
28%
76-77°F
$316 Vol.
17%
78-79°F
$77 Vol.
1%
80-81°F
$260 Vol.
1%
82-83°F
$212 Vol.
1%
84-85°F
$352 Vol.
<1%
86°F or higher
$90 Vol.
71%
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 9 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 uncertainty for Chicago's overnight low on September 9 centers on model spread in the position and strength of a weak high-pressure ridge and associated radiational cooling rates. National Weather Service guidance and ensemble runs show the low hovering near 68–74°F, with slight variations in cloud cover, boundary-layer mixing, and Lake Michigan's moderating influence able to shift the outcome across the tightly bunched 67-or-below and 72–73°F bins that currently lead market-implied odds. Recent upper-air analyses indicate limited moisture and light winds, conditions that favor clearer skies and stronger cooling but remain sensitive to small timing shifts in any passing weak front. Historical September climatology places typical lows in the mid-60s, providing a baseline against which traders weigh the latest model consensus and any afternoon updates from NOAA.
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 9 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 7, 2026, 3:29 AM ET
Volume
$1,328End Date
Sep 9, 2026Market Opened
Sep 7, 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 9 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 uncertainty for Chicago's overnight low on September 9 centers on model spread in the position and strength of a weak high-pressure ridge and associated radiational cooling rates. National Weather Service guidance and ensemble runs show the low hovering near 68–74°F, with slight variations in cloud cover, boundary-layer mixing, and Lake Michigan's moderating influence able to shift the outcome across the tightly bunched 67-or-below and 72–73°F bins that currently lead market-implied odds. Recent upper-air analyses indicate limited moisture and light winds, conditions that favor clearer skies and stronger cooling but remain sensitive to small timing shifts in any passing weak front. Historical September climatology places typical lows in the mid-60s, providing a baseline against which traders weigh the latest model consensus and any afternoon updates from NOAA.
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 9 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
$1,328End Date
Sep 9, 2026Market Opened
Sep 7, 2026, 3:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Forecast uncertainty for Chicago's overnight low on September 9 centers on model spread in the position and strength of a weak high-pressure ridge and associated radiational cooling rates. National Weather Service guidance and ensemble runs show the low hovering near 68–74°F, with slight variations in cloud cover, boundary-layer mixing, and Lake Michigan's moderating influence able to shift the outcome across the tightly bunched 67-or-below and 72–73°F bins that currently lead market-implied odds. Recent upper-air analyses indicate limited moisture and light winds, conditions that favor clearer skies and stronger cooling but remain sensitive to small timing shifts in any passing weak front. Historical September climatology places typical lows in the mid-60s, providing a baseline against which traders weigh the latest model consensus and any afternoon updates from NOAA.
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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