Recent forecast model runs for São Paulo show notable spread in overnight minimum temperatures for September 20, with some ensembles indicating 15–18°C under persistent cloud cover and light rain that limits radiational cooling, while others project 19–21°C amid clearer skies and northerly flow. This uncertainty, amplified by September’s unusually wet pattern that has kept humidity elevated and suppressed typical dry-season temperature swings, explains the near-even market-implied odds between sub-14°C and 23°C+ outcomes. Historical September lows average 12–15°C, but current steering patterns and model consensus favor a milder night near 17–20°C. Final resolution hinges on official INMET station readings at the day’s end.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Sao Paulo on September 20?
Lowest temperature in Sao Paulo on September 20?
13°C or below 93%
23°C or higher 88%
18°C 48%
15°C 39%
NEW
NEW
Sep 20, 2026
13°C or below
93%
14°C
15%
15°C
39%
16°C
39%
17°C
25%
18°C
29%
19°C
39%
20°C
39%
21°C
15%
22°C
15%
23°C or higher
88%
13°C or below 93%
23°C or higher 88%
18°C 48%
15°C 39%
NEW
NEW
Sep 20, 2026
13°C or below
$0 Vol.
93%
14°C
$0 Vol.
15%
15°C
$0 Vol.
39%
16°C
$0 Vol.
39%
17°C
$5 Vol.
25%
18°C
$5 Vol.
29%
19°C
$0 Vol.
39%
20°C
$0 Vol.
39%
21°C
$0 Vol.
15%
22°C
$0 Vol.
15%
23°C or higher
$0 Vol.
88%
This market will resolve to the temperature range that contains the lowest 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 lowest 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 for São Paulo show notable spread in overnight minimum temperatures for September 20, with some ensembles indicating 15–18°C under persistent cloud cover and light rain that limits radiational cooling, while others project 19–21°C amid clearer skies and northerly flow. This uncertainty, amplified by September’s unusually wet pattern that has kept humidity elevated and suppressed typical dry-season temperature swings, explains the near-even market-implied odds between sub-14°C and 23°C+ outcomes. Historical September lows average 12–15°C, but current steering patterns and model consensus favor a milder night near 17–20°C. Final resolution hinges on official INMET station readings at the day’s end.
This market will resolve to the temperature range that contains the lowest 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 lowest 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 lowest 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, 8:29 AM ET
Volume
$10End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest 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 lowest 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 for São Paulo show notable spread in overnight minimum temperatures for September 20, with some ensembles indicating 15–18°C under persistent cloud cover and light rain that limits radiational cooling, while others project 19–21°C amid clearer skies and northerly flow. This uncertainty, amplified by September’s unusually wet pattern that has kept humidity elevated and suppressed typical dry-season temperature swings, explains the near-even market-implied odds between sub-14°C and 23°C+ outcomes. Historical September lows average 12–15°C, but current steering patterns and model consensus favor a milder night near 17–20°C. Final resolution hinges on official INMET station readings at the day’s end.
This market will resolve to the temperature range that contains the lowest 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 lowest 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 lowest 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
$10End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...Recent forecast model runs for São Paulo show notable spread in overnight minimum temperatures for September 20, with some ensembles indicating 15–18°C under persistent cloud cover and light rain that limits radiational cooling, while others project 19–21°C amid clearer skies and northerly flow. This uncertainty, amplified by September’s unusually wet pattern that has kept humidity elevated and suppressed typical dry-season temperature swings, explains the near-even market-implied odds between sub-14°C and 23°C+ outcomes. Historical September lows average 12–15°C, but current steering patterns and model consensus favor a milder night near 17–20°C. Final resolution hinges on official INMET station readings at the day’s end.
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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