Official National Weather Service observations from the Automated Surface Observing System at Chicago O'Hare International Airport confirm the highest temperature on April 20 reached 56-57°F, driving trader consensus to 100% implied probability for that bin amid a dominant cool, cloudy regime. Persistent overcast skies and light precipitation—part of Chicago's record-wet spring with over 10.6 inches of rain since March 1—suppressed highs well below the mid-April climatological average of around 60°F, aligning with NOAA forecast model runs projecting mid-50s peaks under a stable cool air mass. This skin-in-the-game positioning leaves scant room for alternatives, though an extraordinary data validation revision by NWS meteorologists could theoretically challenge it prior to final 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 April 20?
Highest temperature in Chicago on April 20?
56-57°F 100.0%
55°F or below <1%
58-59°F <1%
60-61°F <1%
$85,345 Vol.
$85,345 Vol.
Apr 20, 2026
55°F or below
No
56-57°F
Yes
58-59°F
No
60-61°F
No
62-63°F
No
64-65°F
No
66-67°F
No
68-69°F
No
70-71°F
No
72-73°F
No
74°F or higher
No
56-57°F 100.0%
55°F or below <1%
58-59°F <1%
60-61°F <1%
$85,345 Vol.
$85,345 Vol.
Apr 20, 2026
55°F or below
$16,342 Vol.
No
56-57°F
$19,246 Vol.
Yes
58-59°F
$13,871 Vol.
No
60-61°F
$9,291 Vol.
No
62-63°F
$4,999 Vol.
No
64-65°F
$8,440 Vol.
No
66-67°F
$2,108 Vol.
No
68-69°F
$5,946 Vol.
No
70-71°F
$1,750 Vol.
No
72-73°F
$1,708 Vol.
No
74°F or higher
$1,644 Vol.
No
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 20 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Official National Weather Service observations from the Automated Surface Observing System at Chicago O'Hare International Airport confirm the highest temperature on April 20 reached 56-57°F, driving trader consensus to 100% implied probability for that bin amid a dominant cool, cloudy regime. Persistent overcast skies and light precipitation—part of Chicago's record-wet spring with over 10.6 inches of rain since March 1—suppressed highs well below the mid-April climatological average of around 60°F, aligning with NOAA forecast model runs projecting mid-50s peaks under a stable cool air mass. This skin-in-the-game positioning leaves scant room for alternatives, though an extraordinary data validation revision by NWS meteorologists could theoretically challenge it prior to final resolution.
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 20 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: Apr 18, 2026, 12:40 AM ET
Volume
$85,345End Date
Apr 20, 2026Market Opened
Apr 18, 2026, 12:40 AM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
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 20 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Official National Weather Service observations from the Automated Surface Observing System at Chicago O'Hare International Airport confirm the highest temperature on April 20 reached 56-57°F, driving trader consensus to 100% implied probability for that bin amid a dominant cool, cloudy regime. Persistent overcast skies and light precipitation—part of Chicago's record-wet spring with over 10.6 inches of rain since March 1—suppressed highs well below the mid-April climatological average of around 60°F, aligning with NOAA forecast model runs projecting mid-50s peaks under a stable cool air mass. This skin-in-the-game positioning leaves scant room for alternatives, though an extraordinary data validation revision by NWS meteorologists could theoretically challenge it prior to final resolution.
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 20 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Chicago O'Hare Intl Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$85,345End Date
Apr 20, 2026Market Opened
Apr 18, 2026, 12:40 AM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Official National Weather Service observations from the Automated Surface Observing System at Chicago O'Hare International Airport confirm the highest temperature on April 20 reached 56-57°F, driving trader consensus to 100% implied probability for that bin amid a dominant cool, cloudy regime. Persistent overcast skies and light precipitation—part of Chicago's record-wet spring with over 10.6 inches of rain since March 1—suppressed highs well below the mid-April climatological average of around 60°F, aligning with NOAA forecast model runs projecting mid-50s peaks under a stable cool air mass. This skin-in-the-game positioning leaves scant room for alternatives, though an extraordinary data validation revision by NWS meteorologists could theoretically challenge it prior to final 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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