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icon for Highest temperature in Chicago on August 31?

Highest temperature in Chicago on August 31?

icon for Highest temperature in Chicago on August 31?

Highest temperature in Chicago on August 31?

Aug 29

Aug 30

Aug 31

Aug 29

Aug 30

Aug 31

90-91°F 34%

88-89°F 30%

86-87°F 20%

94-95°F 19%

Polymarket
NEW

90-91°F 34%

88-89°F 30%

86-87°F 20%

94-95°F 19%

Polymarket
NEW

81°F or below

$0 Vol.

1%

82-83°F

$0 Vol.

7%

84-85°F

$0 Vol.

7%

86-87°F

$0 Vol.

20%

88-89°F

$0 Vol.

30%

90-91°F

$0 Vol.

34%

92-93°F

$0 Vol.

16%

94-95°F

$0 Vol.

19%

96-97°F

$0 Vol.

7%

98-99°F

$0 Vol.

7%

100°F or higher

$0 Vol.

4%

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 31 Aug '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. To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F. 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 ensemble model guidance points to a southwesterly flow advecting warmer air into the Chicago area ahead of a weak front, supporting afternoon highs in the upper 80s to low 90s on August 31. Trader weighting between 88–91°F outcomes reflects uncertainty in boundary-layer mixing, cloud cover from residual moisture, and exact timing of peak insolation, which can shift maximum readings by 2–3°F. Historical late-August climatology shows similar setups often peak near 87–90°F, while any increase in dew points or convective inhibition could cap temperatures below model consensus. Updated runs and local observations through August 30 will refine the range ahead of 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 31 Aug '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.

To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.

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
$0
End Date
Aug 31, 2026
Market Opened
Aug 29, 2026, 3:56 AM ET

Resolution Source

https://www.weather.gov/wrh/timeseries?site=kord

Resolver

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 31 Aug '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. To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F. 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 by NOAA at the Chicago O'Hare Intl Airport Station in degrees Fahrenheit on 31 Aug '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. To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F. 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 ensemble model guidance points to a southwesterly flow advecting warmer air into the Chicago area ahead of a weak front, supporting afternoon highs in the upper 80s to low 90s on August 31. Trader weighting between 88–91°F outcomes reflects uncertainty in boundary-layer mixing, cloud cover from residual moisture, and exact timing of peak insolation, which can shift maximum readings by 2–3°F. Historical late-August climatology shows similar setups often peak near 87–90°F, while any increase in dew points or convective inhibition could cap temperatures below model consensus. Updated runs and local observations through August 30 will refine the range ahead of 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 31 Aug '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.

To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.

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
$0
End Date
Aug 31, 2026
Market Opened
Aug 29, 2026, 3:56 AM ET

Resolution Source

https://www.weather.gov/wrh/timeseries?site=kord

Resolver

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 31 Aug '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. To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F. 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.

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Frequently Asked Questions

"Highest temperature in Chicago on August 31?" is a prediction market on Polymarket with 11 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "90-91°F" at 34%, followed by "88-89°F" at 30%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 34¢ implies that the market collectively assigns a 34% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

"Highest temperature in Chicago on August 31?" is a newly created market on Polymarket, launched on Aug 29, 2026. As an early market, this is your opportunity to be among the first traders to set the odds and establish the market's initial price signals. You can also bookmark this page to track volume and trading activity as the market gains traction over time.

To trade on "Highest temperature in Chicago on August 31?," browse the 11 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "Highest temperature in Chicago on August 31?" is "90-91°F" at 34%, meaning the market assigns a 34% chance to that outcome. The next closest outcome is "88-89°F" at 30%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "Highest temperature in Chicago on August 31?" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.