Forecast models for Cape Town on September 16 indicate a maximum temperature most likely between 16–18°C, driven by southerly winds advecting cooler maritime air from the South Atlantic, combined with lingering cloud cover and light rain from a passing frontal system. Recent observations show September averages near 18–19°C, but current conditions feature stronger onshore flow and higher precipitation probability than typical spring patterns, capping daytime warming. Ensemble guidance from sources like ECMWF and GFS shows tight clustering around 16–17°C with limited spread, though small shifts in timing of clearing skies or wind direction could push the daily high toward 18°C or hold it at 16°C. Traders assign near-equal weight to these central outcomes, reflecting genuine forecast uncertainty ahead of updated model runs and official South African Weather Service briefings.
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 16?
18°C 30%
17°C 29%
16°C 17%
14°C 15%
11°C or below
<1%
12°C
4%
13°C
3%
14°C
15%
15°C
5%
16°C
17%
17°C
29%
18°C
30%
19°C
13%
20°C
2%
21°C or higher
<1%
18°C 30%
17°C 29%
16°C 17%
14°C 15%
11°C or below
<1%
12°C
4%
13°C
3%
14°C
15%
15°C
5%
16°C
17%
17°C
29%
18°C
30%
19°C
13%
20°C
2%
21°C or higher
<1%
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 14, 2026, 12:58 AM ET
Resolution Source
https://www.weather.gov/wrh/timeseries?site=factResolver
0x69c47De9D...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.
Resolution Source
https://www.weather.gov/wrh/timeseries?site=factResolver
0x69c47De9D...Forecast models for Cape Town on September 16 indicate a maximum temperature most likely between 16–18°C, driven by southerly winds advecting cooler maritime air from the South Atlantic, combined with lingering cloud cover and light rain from a passing frontal system. Recent observations show September averages near 18–19°C, but current conditions feature stronger onshore flow and higher precipitation probability than typical spring patterns, capping daytime warming. Ensemble guidance from sources like ECMWF and GFS shows tight clustering around 16–17°C with limited spread, though small shifts in timing of clearing skies or wind direction could push the daily high toward 18°C or hold it at 16°C. Traders assign near-equal weight to these central outcomes, reflecting genuine forecast uncertainty ahead of updated model runs and official South African Weather Service briefings.
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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