Current National Weather Service and model guidance for Chicago on July 30 indicate a near-normal late-July pattern, with surface high pressure and light winds supporting daytime highs centered in the mid-80s. Consensus forecasts emphasize modest warming under partly sunny skies, tempered by typical urban heat-island effects and any residual moisture from upstream systems, keeping most outcomes between 84–89 °F. Key variables include the precise timing and strength of any weak frontal boundary, which could increase cloud cover and cap temperatures near 82–83 °F, versus clearer conditions allowing brief excursions to 88–91 °F. Historical climatology shows late-July highs averaging ~84 °F at O’Hare, providing context for why traders assign the highest implied probabilities to the 84–87 °F bins while leaving room for model spread. Updated NWS discussions and 12z model runs tomorrow morning represent the next decision points likely to influence 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 July 30?
86-87°F 36%
88-89°F 30%
84-85°F 18%
90-91°F 11%
81°F or below
<1%
82-83°F
7%
84-85°F
18%
86-87°F
36%
88-89°F
30%
90-91°F
11%
92-93°F
2%
94-95°F
<1%
96-97°F
<1%
98-99°F
<1%
100°F or higher
<1%
86-87°F 36%
88-89°F 30%
84-85°F 18%
90-91°F 11%
81°F or below
<1%
82-83°F
7%
84-85°F
18%
86-87°F
36%
88-89°F
30%
90-91°F
11%
92-93°F
2%
94-95°F
<1%
96-97°F
<1%
98-99°F
<1%
100°F or higher
<1%
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: Jul 28, 2026, 9:03 PM ET
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...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.
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Current National Weather Service and model guidance for Chicago on July 30 indicate a near-normal late-July pattern, with surface high pressure and light winds supporting daytime highs centered in the mid-80s. Consensus forecasts emphasize modest warming under partly sunny skies, tempered by typical urban heat-island effects and any residual moisture from upstream systems, keeping most outcomes between 84–89 °F. Key variables include the precise timing and strength of any weak frontal boundary, which could increase cloud cover and cap temperatures near 82–83 °F, versus clearer conditions allowing brief excursions to 88–91 °F. Historical climatology shows late-July highs averaging ~84 °F at O’Hare, providing context for why traders assign the highest implied probabilities to the 84–87 °F bins while leaving room for model spread. Updated NWS discussions and 12z model runs tomorrow morning represent the next decision points likely to influence 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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