**Persistent high pressure and warm southerly airflow are keeping overnight lows elevated across London during the current heatwave.** Official forecasts from the Met Office and BBC Weather for August 13, 2026, show a minimum around 19–21°C under clear skies and light south-easterly winds, consistent with the market’s tight clustering on 19°C (42.5%) and 20°C (35.5%). Model differences arise mainly from small variations in expected wind speeds and boundary-layer mixing, which influence how much radiational cooling occurs overnight. The urban heat island effect in central London further limits temperature drops compared with rural areas. Normal mid-August minima are typically 14–16°C; the current warm airmass and lack of cloud cover are the main reasons values are several degrees higher. With the market-implied odds reflecting this narrow scientific uncertainty band, traders are pricing the most likely resolution between the two leading outcomes based on the latest ensemble guidance. Updated model runs and official briefings in the final hours before midnight will be the key data points that could shift probabilities between 19°C and 20°C.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in London on August 13?
Lowest temperature in London on August 13?
19°C 43%
20°C 36%
18°C 22%
21°C 4%
NEW
NEW
Aug 13, 2026
14°C or below
<1%
15°C
<1%
16°C
<1%
17°C
3%
18°C
22%
19°C
43%
20°C
36%
21°C
4%
22°C
1%
23°C
<1%
24°C or higher
<1%
19°C 43%
20°C 36%
18°C 22%
21°C 4%
NEW
NEW
Aug 13, 2026
14°C or below
$77 Vol.
<1%
15°C
$132 Vol.
<1%
16°C
$100 Vol.
<1%
17°C
$646 Vol.
3%
18°C
$445 Vol.
22%
19°C
$1,250 Vol.
43%
20°C
$1,593 Vol.
36%
21°C
$378 Vol.
4%
22°C
$171 Vol.
1%
23°C
$266 Vol.
<1%
24°C or higher
$89 Vol.
<1%
This market will resolve based on the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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.**Persistent high pressure and warm southerly airflow are keeping overnight lows elevated across London during the current heatwave.** Official forecasts from the Met Office and BBC Weather for August 13, 2026, show a minimum around 19–21°C under clear skies and light south-easterly winds, consistent with the market’s tight clustering on 19°C (42.5%) and 20°C (35.5%).
Model differences arise mainly from small variations in expected wind speeds and boundary-layer mixing, which influence how much radiational cooling occurs overnight. The urban heat island effect in central London further limits temperature drops compared with rural areas. Normal mid-August minima are typically 14–16°C; the current warm airmass and lack of cloud cover are the main reasons values are several degrees higher.
With the market-implied odds reflecting this narrow scientific uncertainty band, traders are pricing the most likely resolution between the two leading outcomes based on the latest ensemble guidance. Updated model runs and official briefings in the final hours before midnight will be the key data points that could shift probabilities between 19°C and 20°C.
This market will resolve based on the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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 11, 2026, 12:30 AM ET
Volume
$5,146End Date
Aug 13, 2026Market Opened
Aug 11, 2026, 12:30 AM ETResolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...This market will resolve based on the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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.**Persistent high pressure and warm southerly airflow are keeping overnight lows elevated across London during the current heatwave.** Official forecasts from the Met Office and BBC Weather for August 13, 2026, show a minimum around 19–21°C under clear skies and light south-easterly winds, consistent with the market’s tight clustering on 19°C (42.5%) and 20°C (35.5%).
Model differences arise mainly from small variations in expected wind speeds and boundary-layer mixing, which influence how much radiational cooling occurs overnight. The urban heat island effect in central London further limits temperature drops compared with rural areas. Normal mid-August minima are typically 14–16°C; the current warm airmass and lack of cloud cover are the main reasons values are several degrees higher.
With the market-implied odds reflecting this narrow scientific uncertainty band, traders are pricing the most likely resolution between the two leading outcomes based on the latest ensemble guidance. Updated model runs and official briefings in the final hours before midnight will be the key data points that could shift probabilities between 19°C and 20°C.
This market will resolve based on the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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 lowest temperature recorded at the London City Airport Station in degrees Celsius on 13 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the lowest 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
$5,146End Date
Aug 13, 2026Market Opened
Aug 11, 2026, 12:30 AM ETResolution Source
https://www.wunderground.com/history/daily/gb/london/EGLCResolver
0x69c47De9D...**Persistent high pressure and warm southerly airflow are keeping overnight lows elevated across London during the current heatwave.** Official forecasts from the Met Office and BBC Weather for August 13, 2026, show a minimum around 19–21°C under clear skies and light south-easterly winds, consistent with the market’s tight clustering on 19°C (42.5%) and 20°C (35.5%). Model differences arise mainly from small variations in expected wind speeds and boundary-layer mixing, which influence how much radiational cooling occurs overnight. The urban heat island effect in central London further limits temperature drops compared with rural areas. Normal mid-August minima are typically 14–16°C; the current warm airmass and lack of cloud cover are the main reasons values are several degrees higher. With the market-implied odds reflecting this narrow scientific uncertainty band, traders are pricing the most likely resolution between the two leading outcomes based on the latest ensemble guidance. Updated model runs and official briefings in the final hours before midnight will be the key data points that could shift probabilities between 19°C and 20°C.
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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