Recent forecasts for São Paulo on September 21 indicate mostly sunny skies with light northerly winds under stable high pressure, favoring maximum solar heating after cooler, unsettled conditions on the 19th–20th. Official guidance from INMET and regional models such as GFS and ECMWF ensembles show daytime highs clustering between 29–32 °C, with limited cloud cover and dew points supporting efficient temperature rise. Historical September averages near 23–25 °C provide context for the above-normal warmth expected under this pattern. Minor model spread around peak timing and exact boundary-layer mixing keeps probabilities distributed across 29–32 °C, while traders monitor the next model runs and INMET updates for any late adjustments 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 21?
Highest temperature in Sao Paulo on September 21?
31°C 37%
32°C 26%
30°C 23%
33°C 16%
NEW
NEW
Sep 21, 2026
27°C or below
12%
28°C
13%
29°C
12%
30°C
23%
31°C
37%
32°C
24%
33°C
16%
34°C
1%
35°C
<1%
36°C
<1%
37°C or higher
<1%
31°C 37%
32°C 26%
30°C 23%
33°C 16%
NEW
NEW
Sep 21, 2026
27°C or below
$0 Vol.
12%
28°C
$0 Vol.
13%
29°C
$10 Vol.
12%
30°C
$0 Vol.
23%
31°C
$152 Vol.
37%
32°C
$33 Vol.
24%
33°C
$0 Vol.
16%
34°C
$57 Vol.
1%
35°C
$31 Vol.
<1%
36°C
$111 Vol.
<1%
37°C or higher
$50 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 21 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 for São Paulo on September 21 indicate mostly sunny skies with light northerly winds under stable high pressure, favoring maximum solar heating after cooler, unsettled conditions on the 19th–20th. Official guidance from INMET and regional models such as GFS and ECMWF ensembles show daytime highs clustering between 29–32 °C, with limited cloud cover and dew points supporting efficient temperature rise. Historical September averages near 23–25 °C provide context for the above-normal warmth expected under this pattern. Minor model spread around peak timing and exact boundary-layer mixing keeps probabilities distributed across 29–32 °C, while traders monitor the next model runs and INMET updates for any late adjustments 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 21 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 19, 2026, 8:55 AM ET
Volume
$444End Date
Sep 21, 2026Market Opened
Sep 19, 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 21 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 for São Paulo on September 21 indicate mostly sunny skies with light northerly winds under stable high pressure, favoring maximum solar heating after cooler, unsettled conditions on the 19th–20th. Official guidance from INMET and regional models such as GFS and ECMWF ensembles show daytime highs clustering between 29–32 °C, with limited cloud cover and dew points supporting efficient temperature rise. Historical September averages near 23–25 °C provide context for the above-normal warmth expected under this pattern. Minor model spread around peak timing and exact boundary-layer mixing keeps probabilities distributed across 29–32 °C, while traders monitor the next model runs and INMET updates for any late adjustments 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 21 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
$444End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 8:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...Recent forecasts for São Paulo on September 21 indicate mostly sunny skies with light northerly winds under stable high pressure, favoring maximum solar heating after cooler, unsettled conditions on the 19th–20th. Official guidance from INMET and regional models such as GFS and ECMWF ensembles show daytime highs clustering between 29–32 °C, with limited cloud cover and dew points supporting efficient temperature rise. Historical September averages near 23–25 °C provide context for the above-normal warmth expected under this pattern. Minor model spread around peak timing and exact boundary-layer mixing keeps probabilities distributed across 29–32 °C, while traders monitor the next model runs and INMET updates for any late adjustments before resolution.
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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