Trader consensus on Polymarket assigns a 100% implied probability to 21°C as London's highest temperature on April 27, reflecting official Met Office observations from London City Airport—the market's resolution source—which recorded a maximum of 21°C amid mostly sunny conditions and a high-pressure system. This outcome aligns with post-heatwave cooling after early April records near 26°C in Kew Gardens, returning temperatures to mild late-spring norms (seasonal Heathrow average ~15°C) under light southerly winds and low cloud cover. Model forecasts from ECMWF and UKMO had converged on 20-22°C peaks pre-event, with minimal divergence. Realistic challenges are negligible, as provisional data rarely revises post-quality control, barring sensor anomalies confirmed within days.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in London on April 27?
21°C 100.0%
15°C or below <1%
16°C <1%
17°C <1%
$294,925 Vol.
$294,925 Vol.
15°C or below
No
16°C
No
17°C
No
18°C
No
19°C
No
20°C
No
21°C
Yes
22°C
No
23°C
No
24°C
No
25°C or higher
No
21°C 100.0%
15°C or below <1%
16°C <1%
17°C <1%
$294,925 Vol.
$294,925 Vol.
15°C or below
No
16°C
No
17°C
No
18°C
No
19°C
No
20°C
No
21°C
Yes
22°C
No
23°C
No
24°C
No
25°C 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 London City Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/gb/london/EGLC.
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 Celsius (eg, 9°C). 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 25, 2026, 12:07 AM ET
Resolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: 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 London City Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/gb/london/EGLC.
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 Celsius (eg, 9°C). 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/gb/london/EGLCResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Trader consensus on Polymarket assigns a 100% implied probability to 21°C as London's highest temperature on April 27, reflecting official Met Office observations from London City Airport—the market's resolution source—which recorded a maximum of 21°C amid mostly sunny conditions and a high-pressure system. This outcome aligns with post-heatwave cooling after early April records near 26°C in Kew Gardens, returning temperatures to mild late-spring norms (seasonal Heathrow average ~15°C) under light southerly winds and low cloud cover. Model forecasts from ECMWF and UKMO had converged on 20-22°C peaks pre-event, with minimal divergence. Realistic challenges are negligible, as provisional data rarely revises post-quality control, barring sensor anomalies confirmed within days.
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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