Recent National Weather Service and NOAA model guidance points to a strengthening southerly flow ahead of a warm front, supporting afternoon highs in the upper 70s across Chicago on May 18, well above the 71°F climatological normal. Ensemble consensus shows limited spread, with minimal risk of widespread cloud cover or showers suppressing temperatures, though isolated convection could briefly affect readings. This setup aligns with the market’s 75.5% implied probability on 78°F or higher while keeping the 76–77°F tier at 20.5%, as modest timing shifts in the front’s arrival remain the main uncertainty before resolution tomorrow.
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 May 18?
Highest temperature in Chicago on May 18?
78°F or higher 76%
76-77°F 21%
74-75°F 3.7%
72-73°F 1.5%
NEW
$23,709 Vol.
NEW
$23,709 Vol.
May 18, 2026
59°F or below
<1%
60-61°F
<1%
62-63°F
<1%
64-65°F
<1%
66-67°F
<1%
68-69°F
<1%
70-71°F
<1%
72-73°F
2%
74-75°F
4%
76-77°F
21%
78°F or higher
76%
78°F or higher 76%
76-77°F 21%
74-75°F 3.7%
72-73°F 1.5%
NEW
$23,709 Vol.
NEW
$23,709 Vol.
May 18, 2026
59°F or below
$5,126 Vol.
<1%
60-61°F
$7,391 Vol.
<1%
62-63°F
$1,116 Vol.
<1%
64-65°F
$1,476 Vol.
<1%
66-67°F
$1,084 Vol.
<1%
68-69°F
$774 Vol.
<1%
70-71°F
$1,043 Vol.
<1%
72-73°F
$1,076 Vol.
2%
74-75°F
$1,021 Vol.
4%
76-77°F
$1,703 Vol.
21%
78°F or higher
$1,900 Vol.
76%
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 18 May '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.Recent National Weather Service and NOAA model guidance points to a strengthening southerly flow ahead of a warm front, supporting afternoon highs in the upper 70s across Chicago on May 18, well above the 71°F climatological normal. Ensemble consensus shows limited spread, with minimal risk of widespread cloud cover or showers suppressing temperatures, though isolated convection could briefly affect readings. This setup aligns with the market’s 75.5% implied probability on 78°F or higher while keeping the 76–77°F tier at 20.5%, as modest timing shifts in the front’s arrival remain the main uncertainty before resolution tomorrow.
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 18 May '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: May 16, 2026, 12:04 AM ET
Volume
$23,709End Date
May 18, 2026Market Opened
May 16, 2026, 12:04 AM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDThis 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 18 May '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.Recent National Weather Service and NOAA model guidance points to a strengthening southerly flow ahead of a warm front, supporting afternoon highs in the upper 70s across Chicago on May 18, well above the 71°F climatological normal. Ensemble consensus shows limited spread, with minimal risk of widespread cloud cover or showers suppressing temperatures, though isolated convection could briefly affect readings. This setup aligns with the market’s 75.5% implied probability on 78°F or higher while keeping the 76–77°F tier at 20.5%, as modest timing shifts in the front’s arrival remain the main uncertainty before resolution tomorrow.
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 18 May '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
$23,709End Date
May 18, 2026Market Opened
May 16, 2026, 12:04 AM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDRecent National Weather Service and NOAA model guidance points to a strengthening southerly flow ahead of a warm front, supporting afternoon highs in the upper 70s across Chicago on May 18, well above the 71°F climatological normal. Ensemble consensus shows limited spread, with minimal risk of widespread cloud cover or showers suppressing temperatures, though isolated convection could briefly affect readings. This setup aligns with the market’s 75.5% implied probability on 78°F or higher while keeping the 76–77°F tier at 20.5%, as modest timing shifts in the front’s arrival remain the main uncertainty before resolution tomorrow.
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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