National Weather Service forecasts and major model ensembles, including GFS and ECMWF, converge on a Chicago high of 76-77°F for March 21, driven by a potent ridge of high pressure ushering record-challenging warmth into the Midwest amid an unusually mild El Niño winter pattern. Verified soundings and recent radiosonde data confirm favorable upper-level dynamics with strong subsidence and southerly flow, aligning with trader consensus at near-certainty odds. Historical precedents show March norms around 48°F, making this outlier plausible but sensitive to boundary layer mixing; realistic challenges include a sharper cold frontal passage or enhanced cloud cover from lingering Great Lakes moisture, potentially capping temperatures below or spiking them if shear intensifies.
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 March 21?
Highest temperature in Chicago on March 21?
76-77°F 100.0%
59°F or below <1%
60-61°F <1%
62-63°F <1%
$0.00 Vol.
$0.00 Vol.
Mar 21, 2026
59°F or below
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
74-75°F
No
76-77°F
Yes
78°F or higher
No
76-77°F 100.0%
59°F or below <1%
60-61°F <1%
62-63°F <1%
$0.00 Vol.
$0.00 Vol.
Mar 21, 2026
59°F or below
$0 Vol.
No
60-61°F
$0 Vol.
No
62-63°F
$0 Vol.
No
64-65°F
$0 Vol.
No
66-67°F
$0 Vol.
No
68-69°F
$0 Vol.
No
70-71°F
$0 Vol.
No
72-73°F
$0 Vol.
No
74-75°F
$0 Vol.
No
76-77°F
$0 Vol.
Yes
78°F or higher
$0 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 21 Mar '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.National Weather Service forecasts and major model ensembles, including GFS and ECMWF, converge on a Chicago high of 76-77°F for March 21, driven by a potent ridge of high pressure ushering record-challenging warmth into the Midwest amid an unusually mild El Niño winter pattern. Verified soundings and recent radiosonde data confirm favorable upper-level dynamics with strong subsidence and southerly flow, aligning with trader consensus at near-certainty odds. Historical precedents show March norms around 48°F, making this outlier plausible but sensitive to boundary layer mixing; realistic challenges include a sharper cold frontal passage or enhanced cloud cover from lingering Great Lakes moisture, potentially capping temperatures below or spiking them if shear intensifies.
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 21 Mar '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: Mar 17, 2026, 6:02 AM ET
Volume
$0End Date
Mar 21, 2026Market Opened
Mar 17, 2026, 6:02 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 21 Mar '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.National Weather Service forecasts and major model ensembles, including GFS and ECMWF, converge on a Chicago high of 76-77°F for March 21, driven by a potent ridge of high pressure ushering record-challenging warmth into the Midwest amid an unusually mild El Niño winter pattern. Verified soundings and recent radiosonde data confirm favorable upper-level dynamics with strong subsidence and southerly flow, aligning with trader consensus at near-certainty odds. Historical precedents show March norms around 48°F, making this outlier plausible but sensitive to boundary layer mixing; realistic challenges include a sharper cold frontal passage or enhanced cloud cover from lingering Great Lakes moisture, potentially capping temperatures below or spiking them if shear intensifies.
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 21 Mar '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
$0End Date
Mar 21, 2026Market Opened
Mar 17, 2026, 6:02 AM ETResolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
National Weather Service forecasts and major model ensembles, including GFS and ECMWF, converge on a Chicago high of 76-77°F for March 21, driven by a potent ridge of high pressure ushering record-challenging warmth into the Midwest amid an unusually mild El Niño winter pattern. Verified soundings and recent radiosonde data confirm favorable upper-level dynamics with strong subsidence and southerly flow, aligning with trader consensus at near-certainty odds. Historical precedents show March norms around 48°F, making this outlier plausible but sensitive to boundary layer mixing; realistic challenges include a sharper cold frontal passage or enhanced cloud cover from lingering Great Lakes moisture, potentially capping temperatures below or spiking them if shear intensifies.
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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