Recent Met Office guidance indicates sunny intervals and a maximum of 27–28 °C for London on 17 August, following a post-heatwave moderation after peaks near 34 °C earlier in the week. This places the highest temperature squarely between the two leading market outcomes. Key differentiating factors include the precise timing and extent of any residual cloud cover, which modulates incoming solar radiation and surface heating rates, along with light wind patterns that influence boundary-layer mixing and the strength of London’s urban heat island. Ensemble model spreads remain modest at this short lead time, yet small revisions in afternoon insolation or advection of slightly cooler maritime air could easily shift the verified maximum by 1 °C, sustaining the tight 26 °C versus 27 °C trader split.
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 August 17?
Highest temperature in London on August 17?
26°C 40%
27°C 31%
25°C 16%
28°C 11%
NEW
NEW
Aug 17, 2026
20°C or below
<1%
21°C
<1%
22°C
<1%
23°C
1%
24°C
3%
25°C
16%
26°C
40%
27°C
31%
28°C
11%
29°C
2%
30°C or higher
<1%
26°C 40%
27°C 31%
25°C 16%
28°C 11%
NEW
NEW
Aug 17, 2026
20°C or below
$88 Vol.
<1%
21°C
$88 Vol.
<1%
22°C
$93 Vol.
<1%
23°C
$715 Vol.
1%
24°C
$251 Vol.
3%
25°C
$1,142 Vol.
16%
26°C
$757 Vol.
40%
27°C
$1,474 Vol.
31%
28°C
$471 Vol.
11%
29°C
$226 Vol.
2%
30°C or higher
$159 Vol.
<1%
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Recent Met Office guidance indicates sunny intervals and a maximum of 27–28 °C for London on 17 August, following a post-heatwave moderation after peaks near 34 °C earlier in the week. This places the highest temperature squarely between the two leading market outcomes. Key differentiating factors include the precise timing and extent of any residual cloud cover, which modulates incoming solar radiation and surface heating rates, along with light wind patterns that influence boundary-layer mixing and the strength of London’s urban heat island. Ensemble model spreads remain modest at this short lead time, yet small revisions in afternoon insolation or advection of slightly cooler maritime air could easily shift the verified maximum by 1 °C, sustaining the tight 26 °C versus 27 °C trader split.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Market Opened: Aug 15, 2026, 4:04 PM ET
Volume
$5,464End Date
Aug 17, 2026Market Opened
Aug 15, 2026, 4:04 PM ETResolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Recent Met Office guidance indicates sunny intervals and a maximum of 27–28 °C for London on 17 August, following a post-heatwave moderation after peaks near 34 °C earlier in the week. This places the highest temperature squarely between the two leading market outcomes. Key differentiating factors include the precise timing and extent of any residual cloud cover, which modulates incoming solar radiation and surface heating rates, along with light wind patterns that influence boundary-layer mixing and the strength of London’s urban heat island. Ensemble model spreads remain modest at this short lead time, yet small revisions in afternoon insolation or advection of slightly cooler maritime air could easily shift the verified maximum by 1 °C, sustaining the tight 26 °C versus 27 °C trader split.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
This market will resolve to the temperature range that contains the highest temperature recorded at the London City Airport Station in degrees Celsius on 17 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the London City Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Volume
$5,464End Date
Aug 17, 2026Market Opened
Aug 15, 2026, 4:04 PM ETResolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...Recent Met Office guidance indicates sunny intervals and a maximum of 27–28 °C for London on 17 August, following a post-heatwave moderation after peaks near 34 °C earlier in the week. This places the highest temperature squarely between the two leading market outcomes. Key differentiating factors include the precise timing and extent of any residual cloud cover, which modulates incoming solar radiation and surface heating rates, along with light wind patterns that influence boundary-layer mixing and the strength of London’s urban heat island. Ensemble model spreads remain modest at this short lead time, yet small revisions in afternoon insolation or advection of slightly cooler maritime air could easily shift the verified maximum by 1 °C, sustaining the tight 26 °C versus 27 °C trader split.
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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