Persistent cloud cover and widespread showers and thunderstorms forecast for September 19 are the main drivers keeping market-implied odds highest for a maximum of 69°F or below. A strengthening low-pressure system is expected to limit solar heating while southeasterly flow advects cooler, moist air across the Chicago area, with National Weather Service guidance indicating a high near 73°F amid near-100% precipitation chances. These conditions align with recent model consensus showing suppressed daytime maxima relative to the 1991–2020 average high of roughly 75°F for the date. Traders appear to weigh the strong likelihood of rain-cooled temperatures and reduced insolation more heavily than any brief afternoon clearing that could allow modest warming. Updated NWS briefings and real-time observations tomorrow morning will provide the final data for market resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Chicago on September 19?
Highest temperature in Chicago on September 19?
69°F or below 37%
70-71°F 27%
72-73°F 17%
74-75°F 12%
NEW
NEW
Sep 19, 2026
69°F or below
37%
70-71°F
27%
72-73°F
17%
74-75°F
12%
76-77°F
6%
78-79°F
2%
80-81°F
<1%
82-83°F
<1%
84-85°F
<1%
86-87°F
<1%
88°F or higher
<1%
69°F or below 37%
70-71°F 27%
72-73°F 17%
74-75°F 12%
NEW
NEW
Sep 19, 2026
69°F or below
$2,454 Vol.
37%
70-71°F
$2,378 Vol.
27%
72-73°F
$795 Vol.
17%
74-75°F
$856 Vol.
12%
76-77°F
$576 Vol.
6%
78-79°F
$700 Vol.
2%
80-81°F
$475 Vol.
<1%
82-83°F
$111 Vol.
<1%
84-85°F
$111 Vol.
<1%
86-87°F
$111 Vol.
<1%
88°F or higher
$111 Vol.
<1%
This market will resolve to the temperature range that contains the highest 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 highest 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.Persistent cloud cover and widespread showers and thunderstorms forecast for September 19 are the main drivers keeping market-implied odds highest for a maximum of 69°F or below. A strengthening low-pressure system is expected to limit solar heating while southeasterly flow advects cooler, moist air across the Chicago area, with National Weather Service guidance indicating a high near 73°F amid near-100% precipitation chances. These conditions align with recent model consensus showing suppressed daytime maxima relative to the 1991–2020 average high of roughly 75°F for the date. Traders appear to weigh the strong likelihood of rain-cooled temperatures and reduced insolation more heavily than any brief afternoon clearing that could allow modest warming. Updated NWS briefings and real-time observations tomorrow morning will provide the final data for market resolution.
This market will resolve to the temperature range that contains the highest 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 highest 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 highest 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, 2:56 AM ET
Volume
$8,678End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 2:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest 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 highest 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.Persistent cloud cover and widespread showers and thunderstorms forecast for September 19 are the main drivers keeping market-implied odds highest for a maximum of 69°F or below. A strengthening low-pressure system is expected to limit solar heating while southeasterly flow advects cooler, moist air across the Chicago area, with National Weather Service guidance indicating a high near 73°F amid near-100% precipitation chances. These conditions align with recent model consensus showing suppressed daytime maxima relative to the 1991–2020 average high of roughly 75°F for the date. Traders appear to weigh the strong likelihood of rain-cooled temperatures and reduced insolation more heavily than any brief afternoon clearing that could allow modest warming. Updated NWS briefings and real-time observations tomorrow morning will provide the final data for market resolution.
This market will resolve to the temperature range that contains the highest 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 highest 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 highest 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
$8,678End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 2:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kordResolver
0x69c47De9D...Persistent cloud cover and widespread showers and thunderstorms forecast for September 19 are the main drivers keeping market-implied odds highest for a maximum of 69°F or below. A strengthening low-pressure system is expected to limit solar heating while southeasterly flow advects cooler, moist air across the Chicago area, with National Weather Service guidance indicating a high near 73°F amid near-100% precipitation chances. These conditions align with recent model consensus showing suppressed daytime maxima relative to the 1991–2020 average high of roughly 75°F for the date. Traders appear to weigh the strong likelihood of rain-cooled temperatures and reduced insolation more heavily than any brief afternoon clearing that could allow modest warming. Updated NWS briefings and real-time observations tomorrow morning will provide the final data for market resolution.
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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