Recent Met Office and ECMWF model guidance points to a largely settled high-pressure regime over southern England on August 18, favoring partly cloudy to sunny intervals that support daytime maxima near 25–27 °C across London. With the date now within the short-range forecast window, ensemble spreads have narrowed but still reflect modest uncertainty from variable low-level cloud and the precise timing of any weak Atlantic front, keeping the 24 °C, 25 °C, and 26 °C outcomes tightly bunched in trader pricing. These conditions align with typical mid-August climatology once any earlier heat plume has been displaced, while the urban heat-island effect and station-specific measurement (commonly Heathrow) add a small upward bias to recorded maxima. Updated model runs and Met Office briefings over the next 24–48 hours will further refine the most probable peak.
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 18?
Highest temperature in London on August 18?
25°C 31%
24°C 26%
26°C 23%
27°C 9%
NEW
$11,420 Vol.
NEW
$11,420 Vol.
Aug 18, 2026
22°C or below
6%
23°C
9%
24°C
26%
25°C
31%
26°C
23%
27°C
9%
28°C
4%
29°C
1%
30°C
<1%
31°C
<1%
32°C or higher
<1%
25°C 31%
24°C 26%
26°C 23%
27°C 9%
NEW
$11,420 Vol.
NEW
$11,420 Vol.
Aug 18, 2026
22°C or below
$542 Vol.
6%
23°C
$455 Vol.
9%
24°C
$1,705 Vol.
26%
25°C
$3,473 Vol.
31%
26°C
$1,842 Vol.
23%
27°C
$602 Vol.
9%
28°C
$204 Vol.
4%
29°C
$941 Vol.
1%
30°C
$552 Vol.
<1%
31°C
$552 Vol.
<1%
32°C or higher
$552 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 18 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 and ECMWF model guidance points to a largely settled high-pressure regime over southern England on August 18, favoring partly cloudy to sunny intervals that support daytime maxima near 25–27 °C across London. With the date now within the short-range forecast window, ensemble spreads have narrowed but still reflect modest uncertainty from variable low-level cloud and the precise timing of any weak Atlantic front, keeping the 24 °C, 25 °C, and 26 °C outcomes tightly bunched in trader pricing. These conditions align with typical mid-August climatology once any earlier heat plume has been displaced, while the urban heat-island effect and station-specific measurement (commonly Heathrow) add a small upward bias to recorded maxima. Updated model runs and Met Office briefings over the next 24–48 hours will further refine the most probable peak.
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 18 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 18 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 16, 2026, 12:55 AM ET
Volume
$11,420End Date
Aug 18, 2026Market Opened
Aug 16, 2026, 12:55 AM 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 18 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 and ECMWF model guidance points to a largely settled high-pressure regime over southern England on August 18, favoring partly cloudy to sunny intervals that support daytime maxima near 25–27 °C across London. With the date now within the short-range forecast window, ensemble spreads have narrowed but still reflect modest uncertainty from variable low-level cloud and the precise timing of any weak Atlantic front, keeping the 24 °C, 25 °C, and 26 °C outcomes tightly bunched in trader pricing. These conditions align with typical mid-August climatology once any earlier heat plume has been displaced, while the urban heat-island effect and station-specific measurement (commonly Heathrow) add a small upward bias to recorded maxima. Updated model runs and Met Office briefings over the next 24–48 hours will further refine the most probable peak.
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 18 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 18 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
$11,420End Date
Aug 18, 2026Market Opened
Aug 16, 2026, 12:55 AM ETResolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...Recent Met Office and ECMWF model guidance points to a largely settled high-pressure regime over southern England on August 18, favoring partly cloudy to sunny intervals that support daytime maxima near 25–27 °C across London. With the date now within the short-range forecast window, ensemble spreads have narrowed but still reflect modest uncertainty from variable low-level cloud and the precise timing of any weak Atlantic front, keeping the 24 °C, 25 °C, and 26 °C outcomes tightly bunched in trader pricing. These conditions align with typical mid-August climatology once any earlier heat plume has been displaced, while the urban heat-island effect and station-specific measurement (commonly Heathrow) add a small upward bias to recorded maxima. Updated model runs and Met Office briefings over the next 24–48 hours will further refine the most probable peak.
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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