National Weather Service Chicago's latest forecast discussion emphasizes an early Saturday cold frontal passage ushering widespread showers and thunderstorms across northern Illinois on April 4, with temperatures cooling through the day to highs in the 40s amid northwest flow and persistent cloud cover—elevating trader consensus for the "57°F or below" outcome at 28.5% implied probability. Differentiating nearby bins like 58-59°F (22%) and 62-63°F (17.5%) are divergent GFS and ECMWF ensemble projections, where some members delay the front or limit cooling via lingering southerly moisture advection from Thursday's warm front, clustering means near 59°F against the 54.4°F climatological normal at O'Hare. Key variables include frontal timing, instability extent, and post-frontal clearing; watch 12Z model runs for refinements ahead of official observations.
Experimental AI-generated summary referencing Polymarket data · UpdatedHighest temperature in Chicago on April 4?
Highest temperature in Chicago on April 4?
57°F or below 29%
58-59°F 20%
62-63°F 16%
64-65°F 13%
$27,111 Vol.
$27,111 Vol.
57°F or below
29%
58-59°F
20%
60-61°F
12%
62-63°F
16%
64-65°F
13%
66-67°F
9%
68-69°F
9%
70-71°F
5%
72-73°F
<1%
74-75°F
<1%
76°F or higher
<1%
57°F or below 29%
58-59°F 20%
62-63°F 16%
64-65°F 13%
$27,111 Vol.
$27,111 Vol.
57°F or below
29%
58-59°F
20%
60-61°F
12%
62-63°F
16%
64-65°F
13%
66-67°F
9%
68-69°F
9%
70-71°F
5%
72-73°F
<1%
74-75°F
<1%
76°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 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 29, 2026, 4:52 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 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.
Resolution Source
https://www.wunderground.com/history/daily/us/il/chicago/KORDResolver
0x69c47De9D...National Weather Service Chicago's latest forecast discussion emphasizes an early Saturday cold frontal passage ushering widespread showers and thunderstorms across northern Illinois on April 4, with temperatures cooling through the day to highs in the 40s amid northwest flow and persistent cloud cover—elevating trader consensus for the "57°F or below" outcome at 28.5% implied probability. Differentiating nearby bins like 58-59°F (22%) and 62-63°F (17.5%) are divergent GFS and ECMWF ensemble projections, where some members delay the front or limit cooling via lingering southerly moisture advection from Thursday's warm front, clustering means near 59°F against the 54.4°F climatological normal at O'Hare. Key variables include frontal timing, instability extent, and post-frontal clearing; watch 12Z model runs for refinements ahead of official observations.
Experimental AI-generated summary referencing Polymarket data · Updated
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