**A cold front and subsequent polar air mass arriving over São Paulo on September 5–6 are the dominant drivers of trader positioning, with forecasts centering the overnight low near 10–12°C.** Official and ensemble guidance (including Met Office, regional models, and Brazilian meteorological sources) consistently point to a sharp cooldown from the prior week’s 24–32°C highs, driven by persistent cloud cover, widespread light-to-moderate rain, and southeasterly flow advecting cooler maritime air. This setup limits daytime heating while promoting steady nocturnal cooling, with the lowest readings expected in the pre-dawn hours of September 6 under overcast skies. The tight clustering of implied probabilities around 10–12°C (each in the 28–33% range) reflects genuine model spread in the precise minimum: variations arise from differences in boundary-layer moisture, rainfall timing and intensity (which modulates radiative cooling), wind speed, and the exact arrival of the coldest air. Historical September climatology for São Paulo shows average lows near 14–15°C, underscoring how anomalous the current polar outbreak is. Traders appear to be weighting the consensus central tendency while assigning residual probability to slightly warmer or cooler outcomes based on the latest model runs and observational trends as the front moves through. Resolution will hinge on the official overnight minimum recorded at the primary São Paulo station.
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 6?
Lowest temperature in Sao Paulo on September 6?
11°C 33%
10°C 29%
12°C 28%
8°C 26%
NEW
NEW
Sep 6, 2026
6°C or below
1%
7°C
6%
8°C
26%
9°C
26%
10°C
29%
11°C
33%
12°C
28%
13°C
26%
14°C
26%
15°C
10%
16°C or higher
15%
11°C 33%
10°C 29%
12°C 28%
8°C 26%
NEW
NEW
Sep 6, 2026
6°C or below
$15 Vol.
1%
7°C
$15 Vol.
6%
8°C
$0 Vol.
26%
9°C
$0 Vol.
26%
10°C
$0 Vol.
29%
11°C
$0 Vol.
33%
12°C
$0 Vol.
28%
13°C
$0 Vol.
26%
14°C
$0 Vol.
26%
15°C
$5 Vol.
10%
16°C or higher
$5 Vol.
15%
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 6 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 and subsequent polar air mass arriving over São Paulo on September 5–6 are the dominant drivers of trader positioning, with forecasts centering the overnight low near 10–12°C.**
Official and ensemble guidance (including Met Office, regional models, and Brazilian meteorological sources) consistently point to a sharp cooldown from the prior week’s 24–32°C highs, driven by persistent cloud cover, widespread light-to-moderate rain, and southeasterly flow advecting cooler maritime air. This setup limits daytime heating while promoting steady nocturnal cooling, with the lowest readings expected in the pre-dawn hours of September 6 under overcast skies.
The tight clustering of implied probabilities around 10–12°C (each in the 28–33% range) reflects genuine model spread in the precise minimum: variations arise from differences in boundary-layer moisture, rainfall timing and intensity (which modulates radiative cooling), wind speed, and the exact arrival of the coldest air. Historical September climatology for São Paulo shows average lows near 14–15°C, underscoring how anomalous the current polar outbreak is.
Traders appear to be weighting the consensus central tendency while assigning residual probability to slightly warmer or cooler outcomes based on the latest model runs and observational trends as the front moves through. Resolution will hinge on the official overnight minimum recorded at the primary São Paulo station.
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 6 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 4, 2026, 8:29 AM ET
Volume
$40End Date
Sep 6, 2026Market Opened
Sep 4, 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 6 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 and subsequent polar air mass arriving over São Paulo on September 5–6 are the dominant drivers of trader positioning, with forecasts centering the overnight low near 10–12°C.**
Official and ensemble guidance (including Met Office, regional models, and Brazilian meteorological sources) consistently point to a sharp cooldown from the prior week’s 24–32°C highs, driven by persistent cloud cover, widespread light-to-moderate rain, and southeasterly flow advecting cooler maritime air. This setup limits daytime heating while promoting steady nocturnal cooling, with the lowest readings expected in the pre-dawn hours of September 6 under overcast skies.
The tight clustering of implied probabilities around 10–12°C (each in the 28–33% range) reflects genuine model spread in the precise minimum: variations arise from differences in boundary-layer moisture, rainfall timing and intensity (which modulates radiative cooling), wind speed, and the exact arrival of the coldest air. Historical September climatology for São Paulo shows average lows near 14–15°C, underscoring how anomalous the current polar outbreak is.
Traders appear to be weighting the consensus central tendency while assigning residual probability to slightly warmer or cooler outcomes based on the latest model runs and observational trends as the front moves through. Resolution will hinge on the official overnight minimum recorded at the primary São Paulo station.
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 6 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
$40End Date
Sep 6, 2026Market Opened
Sep 4, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=sbgrResolver
0x69c47De9D...**A cold front and subsequent polar air mass arriving over São Paulo on September 5–6 are the dominant drivers of trader positioning, with forecasts centering the overnight low near 10–12°C.** Official and ensemble guidance (including Met Office, regional models, and Brazilian meteorological sources) consistently point to a sharp cooldown from the prior week’s 24–32°C highs, driven by persistent cloud cover, widespread light-to-moderate rain, and southeasterly flow advecting cooler maritime air. This setup limits daytime heating while promoting steady nocturnal cooling, with the lowest readings expected in the pre-dawn hours of September 6 under overcast skies. The tight clustering of implied probabilities around 10–12°C (each in the 28–33% range) reflects genuine model spread in the precise minimum: variations arise from differences in boundary-layer moisture, rainfall timing and intensity (which modulates radiative cooling), wind speed, and the exact arrival of the coldest air. Historical September climatology for São Paulo shows average lows near 14–15°C, underscoring how anomalous the current polar outbreak is. Traders appear to be weighting the consensus central tendency while assigning residual probability to slightly warmer or cooler outcomes based on the latest model runs and observational trends as the front moves through. Resolution will hinge on the official overnight minimum recorded at the primary São Paulo station.
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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