Official observations from National Weather Service stations in the Chicago area recorded a daily maximum of 78–79°F on August 17, 2026, establishing the market consensus. This outcome aligned with a moderating air mass, increased cloud cover, and possible light showers that suppressed daytime heating below the 82–83°F climatological normal for mid-August. Ensemble forecast guidance issued in the preceding 48 hours consistently pointed to upper-70s readings, reducing uncertainty ahead of the close. The 100% implied probability reflects traders' recognition that official verification criteria leave little room for alternative bins once data are finalized. Only a significant revision to the preliminary climate summary or use of an atypical station could alter resolution, both of which remain improbable given standard National Weather Service procedures.
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 August 17?
Highest temperature in Chicago on August 17?
78-79°F 100.0%
73°F or below <1%
74-75°F <1%
76-77°F <1%
$36,365 Vol.
$36,365 Vol.
Aug 17, 2026
73°F or below
<1%
74-75°F
<1%
76-77°F
<1%
78-79°F
100%
80-81°F
<1%
82-83°F
<1%
84-85°F
<1%
86-87°F
<1%
88-89°F
<1%
90-91°F
<1%
92°F or higher
<1%
78-79°F 100.0%
73°F or below <1%
74-75°F <1%
76-77°F <1%
$36,365 Vol.
$36,365 Vol.
Aug 17, 2026
73°F or below
$2,264 Vol.
<1%
74-75°F
$4,341 Vol.
<1%
76-77°F
$7,851 Vol.
<1%
78-79°F
$5,514 Vol.
100%
80-81°F
$5,443 Vol.
<1%
82-83°F
$3,688 Vol.
<1%
84-85°F
$2,786 Vol.
<1%
86-87°F
$2,498 Vol.
<1%
88-89°F
$955 Vol.
<1%
90-91°F
$448 Vol.
<1%
92°F or higher
$578 Vol.
<1%
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.Official observations from National Weather Service stations in the Chicago area recorded a daily maximum of 78–79°F on August 17, 2026, establishing the market consensus. This outcome aligned with a moderating air mass, increased cloud cover, and possible light showers that suppressed daytime heating below the 82–83°F climatological normal for mid-August. Ensemble forecast guidance issued in the preceding 48 hours consistently pointed to upper-70s readings, reducing uncertainty ahead of the close. The 100% implied probability reflects traders' recognition that official verification criteria leave little room for alternative bins once data are finalized. Only a significant revision to the preliminary climate summary or use of an atypical station could alter resolution, both of which remain improbable given standard National Weather Service procedures.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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: Aug 15, 2026, 9:56 PM ET
Volume
$36,365End Date
Aug 17, 2026Market Opened
Aug 15, 2026, 9:56 PM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.Official observations from National Weather Service stations in the Chicago area recorded a daily maximum of 78–79°F on August 17, 2026, establishing the market consensus. This outcome aligned with a moderating air mass, increased cloud cover, and possible light showers that suppressed daytime heating below the 82–83°F climatological normal for mid-August. Ensemble forecast guidance issued in the preceding 48 hours consistently pointed to upper-70s readings, reducing uncertainty ahead of the close. The 100% implied probability reflects traders' recognition that official verification criteria leave little room for alternative bins once data are finalized. Only a significant revision to the preliminary climate summary or use of an atypical station could alter resolution, both of which remain improbable given standard National Weather Service procedures.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.
This market will resolve to the temperature range that contains the highest temperature recorded at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Chicago O'Hare Intl Airport Station, available here: https://www.wunderground.com/history/daily/us/il/chicago/KORD.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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
$36,365End Date
Aug 17, 2026Market Opened
Aug 15, 2026, 9:56 PM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Official observations from National Weather Service stations in the Chicago area recorded a daily maximum of 78–79°F on August 17, 2026, establishing the market consensus. This outcome aligned with a moderating air mass, increased cloud cover, and possible light showers that suppressed daytime heating below the 82–83°F climatological normal for mid-August. Ensemble forecast guidance issued in the preceding 48 hours consistently pointed to upper-70s readings, reducing uncertainty ahead of the close. The 100% implied probability reflects traders' recognition that official verification criteria leave little room for alternative bins once data are finalized. Only a significant revision to the preliminary climate summary or use of an atypical station could alter resolution, both of which remain improbable given standard National Weather Service procedures.
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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