Recent forecast model runs from agencies like the Met Office and local meteorological services indicate a high temperature for São Paulo on September 20 most likely in the 23–26°C range, with persistent cloud cover, northerly winds, and a 30–40% chance of light rain or thunderstorms moderating daytime heating. These conditions align with the month's below-average temperatures so far and typical early-spring patterns influenced by regional atmospheric circulation. Divergence among models on exact cloud thickness and precipitation timing creates genuine uncertainty, which is reflected in the closely matched market-implied odds favoring 23–25°C outcomes. Updated model guidance expected in the next 24–48 hours could shift probabilities if clearer skies develop.
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 20?
Highest temperature in Sao Paulo on September 20?
23°C 39%
21°C or below 30%
22°C 30%
24°C 20%
NEW
NEW
Sep 20, 2026
21°C or below
30%
22°C
30%
23°C
39%
24°C
20%
25°C
19%
26°C
18%
27°C
14%
28°C
7%
29°C
4%
30°C
4%
31°C or higher
4%
23°C 39%
21°C or below 30%
22°C 30%
24°C 20%
NEW
NEW
Sep 20, 2026
21°C or below
$0 Vol.
30%
22°C
$0 Vol.
30%
23°C
$0 Vol.
39%
24°C
$0 Vol.
20%
25°C
$0 Vol.
19%
26°C
$7 Vol.
18%
27°C
$0 Vol.
14%
28°C
$40 Vol.
7%
29°C
$0 Vol.
4%
30°C
$0 Vol.
4%
31°C or higher
$0 Vol.
4%
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 20 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 forecast model runs from agencies like the Met Office and local meteorological services indicate a high temperature for São Paulo on September 20 most likely in the 23–26°C range, with persistent cloud cover, northerly winds, and a 30–40% chance of light rain or thunderstorms moderating daytime heating. These conditions align with the month's below-average temperatures so far and typical early-spring patterns influenced by regional atmospheric circulation. Divergence among models on exact cloud thickness and precipitation timing creates genuine uncertainty, which is reflected in the closely matched market-implied odds favoring 23–25°C outcomes. Updated model guidance expected in the next 24–48 hours could shift probabilities if clearer skies develop.
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 20 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 18, 2026, 8:55 AM ET
Volume
$47End Date
Sep 20, 2026Market Opened
Sep 18, 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 20 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 forecast model runs from agencies like the Met Office and local meteorological services indicate a high temperature for São Paulo on September 20 most likely in the 23–26°C range, with persistent cloud cover, northerly winds, and a 30–40% chance of light rain or thunderstorms moderating daytime heating. These conditions align with the month's below-average temperatures so far and typical early-spring patterns influenced by regional atmospheric circulation. Divergence among models on exact cloud thickness and precipitation timing creates genuine uncertainty, which is reflected in the closely matched market-implied odds favoring 23–25°C outcomes. Updated model guidance expected in the next 24–48 hours could shift probabilities if clearer skies develop.
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 20 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
$47End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...Recent forecast model runs from agencies like the Met Office and local meteorological services indicate a high temperature for São Paulo on September 20 most likely in the 23–26°C range, with persistent cloud cover, northerly winds, and a 30–40% chance of light rain or thunderstorms moderating daytime heating. These conditions align with the month's below-average temperatures so far and typical early-spring patterns influenced by regional atmospheric circulation. Divergence among models on exact cloud thickness and precipitation timing creates genuine uncertainty, which is reflected in the closely matched market-implied odds favoring 23–25°C outcomes. Updated model guidance expected in the next 24–48 hours could shift probabilities if clearer skies develop.
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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