Recent National Weather Service and model guidance for Chicago point to a moderating air mass and increased cloud cover limiting daytime heating on August 17, positioning the highest temperature most likely in the upper 70s to low 80s. Ensemble forecasts show highs near or slightly below seasonal normals of 82–83°F, with 80–81°F emerging as the modal outcome amid variable steering patterns and possible showers. Market-implied odds align with this consensus while assigning meaningful probability to 78–79°F if cooler boundary-layer conditions prevail, reflecting traders’ incorporation of forecast spread and historical variability in mid-August maxima. Updated model runs and NWS briefings expected overnight will provide the next key data points for 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 August 17?
Highest temperature in Chicago on August 17?
80-81°F 48%
78-79°F 28%
82-83°F 17%
76-77°F 7%
NEW
NEW
Aug 17, 2026
73°F or below
<1%
74-75°F
2%
76-77°F
7%
78-79°F
28%
80-81°F
48%
82-83°F
17%
84-85°F
4%
86-87°F
2%
88-89°F
<1%
90-91°F
<1%
92°F or higher
<1%
80-81°F 48%
78-79°F 28%
82-83°F 17%
76-77°F 7%
NEW
NEW
Aug 17, 2026
73°F or below
$315 Vol.
<1%
74-75°F
$134 Vol.
2%
76-77°F
$178 Vol.
7%
78-79°F
$200 Vol.
28%
80-81°F
$627 Vol.
48%
82-83°F
$126 Vol.
17%
84-85°F
$91 Vol.
4%
86-87°F
$114 Vol.
2%
88-89°F
$178 Vol.
<1%
90-91°F
$332 Vol.
<1%
92°F or higher
$410 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.Recent National Weather Service and model guidance for Chicago point to a moderating air mass and increased cloud cover limiting daytime heating on August 17, positioning the highest temperature most likely in the upper 70s to low 80s. Ensemble forecasts show highs near or slightly below seasonal normals of 82–83°F, with 80–81°F emerging as the modal outcome amid variable steering patterns and possible showers. Market-implied odds align with this consensus while assigning meaningful probability to 78–79°F if cooler boundary-layer conditions prevail, reflecting traders’ incorporation of forecast spread and historical variability in mid-August maxima. Updated model runs and NWS briefings expected overnight will provide the next key data points for resolution.
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
$2,705End 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.Recent National Weather Service and model guidance for Chicago point to a moderating air mass and increased cloud cover limiting daytime heating on August 17, positioning the highest temperature most likely in the upper 70s to low 80s. Ensemble forecasts show highs near or slightly below seasonal normals of 82–83°F, with 80–81°F emerging as the modal outcome amid variable steering patterns and possible showers. Market-implied odds align with this consensus while assigning meaningful probability to 78–79°F if cooler boundary-layer conditions prevail, reflecting traders’ incorporation of forecast spread and historical variability in mid-August maxima. Updated model runs and NWS briefings expected overnight will provide the next key data points for resolution.
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
$2,705End Date
Aug 17, 2026Market Opened
Aug 15, 2026, 9:56 PM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Recent National Weather Service and model guidance for Chicago point to a moderating air mass and increased cloud cover limiting daytime heating on August 17, positioning the highest temperature most likely in the upper 70s to low 80s. Ensemble forecasts show highs near or slightly below seasonal normals of 82–83°F, with 80–81°F emerging as the modal outcome amid variable steering patterns and possible showers. Market-implied odds align with this consensus while assigning meaningful probability to 78–79°F if cooler boundary-layer conditions prevail, reflecting traders’ incorporation of forecast spread and historical variability in mid-August maxima. Updated model runs and NWS briefings expected overnight will provide the next key data points for 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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