Latest National Weather Service forecasts for Chicago's O'Hare International Airport—the official measurement site—project a high temperature of exactly 41°F on March 23, driven by persistent northerly winds and a deep upper-level trough over the Midwest, aligning model ensembles from GFS and ECMWF that show limited diurnal warming under cloudy skies. Historical late-March averages hover around 45°F, but this setup echoes recent cool anomalies from lingering winter patterns, solidifying trader consensus at near-certainty for 40-41°F. Realistic challenges include an unforeseen shortwave ridge amplifying downslope warming or a model bust from underresolved boundary layer effects, potentially pushing peaks to 44°F+, though probabilities remain under 1% per current guidance.
Experimental AI-generated summary referencing Polymarket data · UpdatedHighest temperature in Chicago on March 23?
Highest temperature in Chicago on March 23?
40-41°F 100.0%
35°F or below <1%
36-37°F <1%
38-39°F <1%
$0.00 Vol.
$0.00 Vol.
35°F or below
No
36-37°F
No
38-39°F
No
40-41°F
Yes
42-43°F
No
44-45°F
No
46-47°F
No
48-49°F
No
50-51°F
No
52-53°F
No
54°F or higher
No
40-41°F 100.0%
35°F or below <1%
36-37°F <1%
38-39°F <1%
$0.00 Vol.
$0.00 Vol.
35°F or below
No
36-37°F
No
38-39°F
No
40-41°F
Yes
42-43°F
No
44-45°F
No
46-47°F
No
48-49°F
No
50-51°F
No
52-53°F
No
54°F or higher
No
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 19, 2026, 6:02 AM ET
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...Latest National Weather Service forecasts for Chicago's O'Hare International Airport—the official measurement site—project a high temperature of exactly 41°F on March 23, driven by persistent northerly winds and a deep upper-level trough over the Midwest, aligning model ensembles from GFS and ECMWF that show limited diurnal warming under cloudy skies. Historical late-March averages hover around 45°F, but this setup echoes recent cool anomalies from lingering winter patterns, solidifying trader consensus at near-certainty for 40-41°F. Realistic challenges include an unforeseen shortwave ridge amplifying downslope warming or a model bust from underresolved boundary layer effects, potentially pushing peaks to 44°F+, though probabilities remain under 1% per current guidance.
Experimental AI-generated summary referencing Polymarket data · Updated
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