Recent forecasts from multiple models indicate a cold front and persistent cloud cover will limit daytime heating in São Paulo on September 23, with official guidance pointing to highs of 15–17°C amid widespread rain and southerly flow. This aligns with the broader September 2026 pattern of record rainfall driven by repeated polar air intrusions and an Atlantic dipole favoring frontal passages, which has already kept temperatures well below the long-term September average high near 26°C. Traders are pricing the tight 15–18°C cluster most heavily because ensemble runs show limited variability once the front arrives, though slight shifts in timing or cloud thickness could push the daily maximum toward 18°C or hold it near 15°C. Updated NHC-equivalent regional guidance and overnight observations will refine the final outcome before resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Sao Paulo on September 23?
Highest temperature in Sao Paulo on September 23?
17°C 33%
16°C 28%
15°C 16%
18°C 16%
NEW
NEW
Sep 23, 2026
13°C or below
2%
14°C
5%
15°C
16%
16°C
28%
17°C
33%
18°C
16%
19°C
5%
20°C
2%
21°C
3%
22°C
<1%
23°C or higher
<1%
17°C 33%
16°C 28%
15°C 16%
18°C 16%
NEW
NEW
Sep 23, 2026
13°C or below
$111 Vol.
2%
14°C
$17 Vol.
5%
15°C
$297 Vol.
16%
16°C
$164 Vol.
28%
17°C
$188 Vol.
33%
18°C
$101 Vol.
16%
19°C
$144 Vol.
5%
20°C
$100 Vol.
2%
21°C
$308 Vol.
3%
22°C
$105 Vol.
<1%
23°C or higher
$105 Vol.
<1%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 23 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=sbgr
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.Recent forecasts from multiple models indicate a cold front and persistent cloud cover will limit daytime heating in São Paulo on September 23, with official guidance pointing to highs of 15–17°C amid widespread rain and southerly flow. This aligns with the broader September 2026 pattern of record rainfall driven by repeated polar air intrusions and an Atlantic dipole favoring frontal passages, which has already kept temperatures well below the long-term September average high near 26°C. Traders are pricing the tight 15–18°C cluster most heavily because ensemble runs show limited variability once the front arrives, though slight shifts in timing or cloud thickness could push the daily maximum toward 18°C or hold it near 15°C. Updated NHC-equivalent regional guidance and overnight observations will refine the final outcome before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 23 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=sbgr
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=sbgr
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 21, 2026, 8:55 AM ET
Volume
$1,639End Date
Sep 23, 2026Market Opened
Sep 21, 2026, 8:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 23 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=sbgr
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.Recent forecasts from multiple models indicate a cold front and persistent cloud cover will limit daytime heating in São Paulo on September 23, with official guidance pointing to highs of 15–17°C amid widespread rain and southerly flow. This aligns with the broader September 2026 pattern of record rainfall driven by repeated polar air intrusions and an Atlantic dipole favoring frontal passages, which has already kept temperatures well below the long-term September average high near 26°C. Traders are pricing the tight 15–18°C cluster most heavily because ensemble runs show limited variability once the front arrives, though slight shifts in timing or cloud thickness could push the daily maximum toward 18°C or hold it near 15°C. Updated NHC-equivalent regional guidance and overnight observations will refine the final outcome before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 23 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=sbgr
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=sbgr
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
$1,639End Date
Sep 23, 2026Market Opened
Sep 21, 2026, 8:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...Recent forecasts from multiple models indicate a cold front and persistent cloud cover will limit daytime heating in São Paulo on September 23, with official guidance pointing to highs of 15–17°C amid widespread rain and southerly flow. This aligns with the broader September 2026 pattern of record rainfall driven by repeated polar air intrusions and an Atlantic dipole favoring frontal passages, which has already kept temperatures well below the long-term September average high near 26°C. Traders are pricing the tight 15–18°C cluster most heavily because ensemble runs show limited variability once the front arrives, though slight shifts in timing or cloud thickness could push the daily maximum toward 18°C or hold it near 15°C. Updated NHC-equivalent regional guidance and overnight observations will refine the final outcome before resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
Beware of external links.
Beware of external links.
Frequently Asked Questions