Current forecast models from sources including the GFS and ECMWF consensus point to a São Paulo minimum temperature near 18–20°C on September 20, shaped by northerly winds and persistent cloud cover that limit radiative cooling overnight. A low-pressure system over the continent is driving increased moisture and scattered showers, which raise dew points and reduce the diurnal temperature range compared with clear-sky September norms around 12°C. Model spread remains modest, but small shifts in timing of cloud breaks or wind direction could nudge the exact low by 1–2°C, sustaining trader balance between the closely matched 13°C-or-below and 23°C-or-higher outcomes while favoring the 18–20°C cluster. Updated runs tomorrow morning will refine these variables ahead of market resolution.
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 92%
23°C or higher 92%
18°C 48%
15°C 39%
NEW
NEW
Sep 20, 2026
13°C or below
92%
14°C
17%
15°C
39%
16°C
39%
17°C
39%
18°C
29%
19°C
39%
20°C
39%
21°C
17%
22°C
17%
23°C or higher
92%
13°C or below 92%
23°C or higher 92%
18°C 48%
15°C 39%
NEW
NEW
Sep 20, 2026
13°C or below
$0 Vol.
92%
14°C
$0 Vol.
17%
15°C
$0 Vol.
39%
16°C
$0 Vol.
39%
17°C
$0 Vol.
39%
18°C
$5 Vol.
29%
19°C
$0 Vol.
39%
20°C
$0 Vol.
39%
21°C
$0 Vol.
17%
22°C
$0 Vol.
17%
23°C or higher
$0 Vol.
92%
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.Current forecast models from sources including the GFS and ECMWF consensus point to a São Paulo minimum temperature near 18–20°C on September 20, shaped by northerly winds and persistent cloud cover that limit radiative cooling overnight. A low-pressure system over the continent is driving increased moisture and scattered showers, which raise dew points and reduce the diurnal temperature range compared with clear-sky September norms around 12°C. Model spread remains modest, but small shifts in timing of cloud breaks or wind direction could nudge the exact low by 1–2°C, sustaining trader balance between the closely matched 13°C-or-below and 23°C-or-higher outcomes while favoring the 18–20°C cluster. Updated runs tomorrow morning will refine these variables ahead of market resolution.
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
$5End 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.Current forecast models from sources including the GFS and ECMWF consensus point to a São Paulo minimum temperature near 18–20°C on September 20, shaped by northerly winds and persistent cloud cover that limit radiative cooling overnight. A low-pressure system over the continent is driving increased moisture and scattered showers, which raise dew points and reduce the diurnal temperature range compared with clear-sky September norms around 12°C. Model spread remains modest, but small shifts in timing of cloud breaks or wind direction could nudge the exact low by 1–2°C, sustaining trader balance between the closely matched 13°C-or-below and 23°C-or-higher outcomes while favoring the 18–20°C cluster. Updated runs tomorrow morning will refine these variables ahead of market resolution.
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
$5End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...Current forecast models from sources including the GFS and ECMWF consensus point to a São Paulo minimum temperature near 18–20°C on September 20, shaped by northerly winds and persistent cloud cover that limit radiative cooling overnight. A low-pressure system over the continent is driving increased moisture and scattered showers, which raise dew points and reduce the diurnal temperature range compared with clear-sky September norms around 12°C. Model spread remains modest, but small shifts in timing of cloud breaks or wind direction could nudge the exact low by 1–2°C, sustaining trader balance between the closely matched 13°C-or-below and 23°C-or-higher outcomes while favoring the 18–20°C cluster. Updated runs tomorrow morning will refine these variables ahead of market 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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