Forecast models from sources including GFS and regional guidance indicate a high of 19–21°C for Cape Town on September 18 under clear skies and moderate southeasterly winds associated with a stable high-pressure ridge. These conditions favor daytime warming without significant cloud cover or frontal systems, aligning with the market's heavy weighting toward 21°C (53%) and 22°C (30.5%). September climatology shows average maxima near 19°C, so the current setup represents slightly above-normal spring warmth driven by dry air advection rather than heat waves. Minor model spread in peak timing and exact wind strength creates residual probability for 19–20°C outcomes, while stronger warming would require unexpected pressure changes before resolution. Updated model runs and South African Weather Service observations over the next 48 hours will refine the exact maximum.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Cape Town on September 18?
Highest temperature in Cape Town on September 18?
21°C 53%
22°C 31%
23°C 20%
24°C 18%
NEW
NEW
Sep 18, 2026
16°C or below
<1%
17°C
4%
18°C
3%
19°C
14%
20°C
17%
21°C
53%
22°C
31%
23°C
20%
24°C
18%
25°C
2%
26°C or higher
<1%
21°C 53%
22°C 31%
23°C 20%
24°C 18%
NEW
NEW
Sep 18, 2026
16°C or below
$0 Vol.
<1%
17°C
$0 Vol.
4%
18°C
$5 Vol.
3%
19°C
$5 Vol.
14%
20°C
$5 Vol.
17%
21°C
$109 Vol.
53%
22°C
$33 Vol.
31%
23°C
$0 Vol.
20%
24°C
$0 Vol.
18%
25°C
$0 Vol.
2%
26°C or higher
$0 Vol.
<1%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Cape Town International Airport Station in degrees Celsius on 18 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Forecast models from sources including GFS and regional guidance indicate a high of 19–21°C for Cape Town on September 18 under clear skies and moderate southeasterly winds associated with a stable high-pressure ridge. These conditions favor daytime warming without significant cloud cover or frontal systems, aligning with the market's heavy weighting toward 21°C (53%) and 22°C (30.5%). September climatology shows average maxima near 19°C, so the current setup represents slightly above-normal spring warmth driven by dry air advection rather than heat waves. Minor model spread in peak timing and exact wind strength creates residual probability for 19–20°C outcomes, while stronger warming would require unexpected pressure changes before resolution. Updated model runs and South African Weather Service observations over the next 48 hours will refine the exact maximum.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Cape Town International Airport Station in degrees Celsius on 18 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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: Sep 16, 2026, 12:58 AM ET
Volume
$157End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:58 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=factResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Cape Town International Airport Station in degrees Celsius on 18 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Forecast models from sources including GFS and regional guidance indicate a high of 19–21°C for Cape Town on September 18 under clear skies and moderate southeasterly winds associated with a stable high-pressure ridge. These conditions favor daytime warming without significant cloud cover or frontal systems, aligning with the market's heavy weighting toward 21°C (53%) and 22°C (30.5%). September climatology shows average maxima near 19°C, so the current setup represents slightly above-normal spring warmth driven by dry air advection rather than heat waves. Minor model spread in peak timing and exact wind strength creates residual probability for 19–20°C outcomes, while stronger warming would require unexpected pressure changes before resolution. Updated model runs and South African Weather Service observations over the next 48 hours will refine the exact maximum.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Cape Town International Airport Station in degrees Celsius on 18 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=fact
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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
$157End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:58 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=factResolver
0x69c47De9D...Forecast models from sources including GFS and regional guidance indicate a high of 19–21°C for Cape Town on September 18 under clear skies and moderate southeasterly winds associated with a stable high-pressure ridge. These conditions favor daytime warming without significant cloud cover or frontal systems, aligning with the market's heavy weighting toward 21°C (53%) and 22°C (30.5%). September climatology shows average maxima near 19°C, so the current setup represents slightly above-normal spring warmth driven by dry air advection rather than heat waves. Minor model spread in peak timing and exact wind strength creates residual probability for 19–20°C outcomes, while stronger warming would require unexpected pressure changes before resolution. Updated model runs and South African Weather Service observations over the next 48 hours will refine the exact maximum.
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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