A cold front advancing into São Paulo on September 23, 2026, with southerly winds and widespread rain, is the main driver keeping the lowest temperature in the low-to-mid teens Celsius and splitting trader probabilities across 13–14°C outcomes. Official model consensus from GFS and similar guidance shows overnight lows near 12–14°C under overcast skies, as reduced radiative cooling from cloud cover and moisture offsets some of the polar air advection. Historical September baselines average 15–17°C lows, but the current setup favors a sharper drop; however, minor shifts in front timing or wind direction could push the minimum above or below key thresholds. Final ensemble runs and local observations on the 23rd will resolve remaining uncertainty in the market-implied odds.
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 23?
Lowest temperature in Sao Paulo on September 23?
18°C or higher 57%
8°C or below 48%
14°C 44%
13°C 31%
NEW
NEW
Sep 23, 2026
8°C or below
48%
9°C
8%
10°C
21%
11°C
21%
12°C
21%
13°C
31%
14°C
30%
15°C
22%
16°C
21%
17°C
4%
18°C or higher
57%
18°C or higher 57%
8°C or below 48%
14°C 44%
13°C 31%
NEW
NEW
Sep 23, 2026
8°C or below
$50 Vol.
48%
9°C
$40 Vol.
8%
10°C
$0 Vol.
21%
11°C
$0 Vol.
21%
12°C
$0 Vol.
21%
13°C
$0 Vol.
31%
14°C
$7 Vol.
30%
15°C
$0 Vol.
22%
16°C
$0 Vol.
21%
17°C
$15 Vol.
4%
18°C or higher
$100 Vol.
57%
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 23 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.A cold front advancing into São Paulo on September 23, 2026, with southerly winds and widespread rain, is the main driver keeping the lowest temperature in the low-to-mid teens Celsius and splitting trader probabilities across 13–14°C outcomes. Official model consensus from GFS and similar guidance shows overnight lows near 12–14°C under overcast skies, as reduced radiative cooling from cloud cover and moisture offsets some of the polar air advection. Historical September baselines average 15–17°C lows, but the current setup favors a sharper drop; however, minor shifts in front timing or wind direction could push the minimum above or below key thresholds. Final ensemble runs and local observations on the 23rd will resolve remaining uncertainty in the market-implied odds.
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 23 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 21, 2026, 8:29 AM ET
Volume
$213End Date
Sep 23, 2026Market Opened
Sep 21, 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 23 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.A cold front advancing into São Paulo on September 23, 2026, with southerly winds and widespread rain, is the main driver keeping the lowest temperature in the low-to-mid teens Celsius and splitting trader probabilities across 13–14°C outcomes. Official model consensus from GFS and similar guidance shows overnight lows near 12–14°C under overcast skies, as reduced radiative cooling from cloud cover and moisture offsets some of the polar air advection. Historical September baselines average 15–17°C lows, but the current setup favors a sharper drop; however, minor shifts in front timing or wind direction could push the minimum above or below key thresholds. Final ensemble runs and local observations on the 23rd will resolve remaining uncertainty in the market-implied odds.
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 23 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
$213End Date
Sep 23, 2026Market Opened
Sep 21, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...A cold front advancing into São Paulo on September 23, 2026, with southerly winds and widespread rain, is the main driver keeping the lowest temperature in the low-to-mid teens Celsius and splitting trader probabilities across 13–14°C outcomes. Official model consensus from GFS and similar guidance shows overnight lows near 12–14°C under overcast skies, as reduced radiative cooling from cloud cover and moisture offsets some of the polar air advection. Historical September baselines average 15–17°C lows, but the current setup favors a sharper drop; however, minor shifts in front timing or wind direction could push the minimum above or below key thresholds. Final ensemble runs and local observations on the 23rd will resolve remaining uncertainty in the market-implied odds.
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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