Trader consensus on Polymarket heavily favors 29°C (44.5% implied probability) as the highest temperature in São Paulo on April 18, driven by the latest forecasts from Brazil's National Institute of Meteorology (INMET) and Climatempo, projecting daytime highs of 28–30°C under clear skies and a subtropical high-pressure ridge promoting solar heating with low humidity around 50–60%. Recent observations on April 17 showed highs near 30°C amid lingering summer warmth—0.34°C above historical norms per INMET's summer recap—positioning 30°C (19%) and 28°C (17%) as strong contenders if minor cloud cover or sea breezes intervene. April climatology typically sees highs of 24–27°C on the Saffir-Simpson-irrelevant scale here, but this warm anomaly sustains elevated odds; extremes like 34°C+ (<1%) remain unlikely absent unusual advection. Updated model runs expected overnight could refine these probabilities ahead of official station measurements at Congonhas Airport.
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 April 18?
Highest temperature in Sao Paulo on April 18?
29°C 42%
30°C 19%
28°C 19%
27°C 10%
NEW
$11,887 Vol.
NEW
$11,887 Vol.
Apr 18, 2026
24°C or below
1%
25°C
<1%
26°C
3%
27°C
10%
28°C
19%
29°C
42%
30°C
19%
31°C
8%
32°C
3%
33°C
<1%
34°C or higher
1%
29°C 42%
30°C 19%
28°C 19%
27°C 10%
NEW
$11,887 Vol.
NEW
$11,887 Vol.
Apr 18, 2026
24°C or below
$1,565 Vol.
1%
25°C
$1,401 Vol.
<1%
26°C
$1,069 Vol.
3%
27°C
$811 Vol.
10%
28°C
$573 Vol.
19%
29°C
$1,174 Vol.
42%
30°C
$1,378 Vol.
19%
31°C
$1,442 Vol.
8%
32°C
$885 Vol.
3%
33°C
$795 Vol.
<1%
34°C or higher
$843 Vol.
1%
This market will resolve to the temperature range that contains the highest temperature recorded at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 18 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Trader consensus on Polymarket heavily favors 29°C (44.5% implied probability) as the highest temperature in São Paulo on April 18, driven by the latest forecasts from Brazil's National Institute of Meteorology (INMET) and Climatempo, projecting daytime highs of 28–30°C under clear skies and a subtropical high-pressure ridge promoting solar heating with low humidity around 50–60%. Recent observations on April 17 showed highs near 30°C amid lingering summer warmth—0.34°C above historical norms per INMET's summer recap—positioning 30°C (19%) and 28°C (17%) as strong contenders if minor cloud cover or sea breezes intervene. April climatology typically sees highs of 24–27°C on the Saffir-Simpson-irrelevant scale here, but this warm anomaly sustains elevated odds; extremes like 34°C+ (<1%) remain unlikely absent unusual advection. Updated model runs expected overnight could refine these probabilities ahead of official station measurements at Congonhas Airport.
This market will resolve to the temperature range that contains the highest temperature recorded at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 18 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: Apr 16, 2026, 12:26 AM ET
Volume
$11,887End Date
Apr 18, 2026Market Opened
Apr 16, 2026, 12:26 AM ETResolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 18 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Trader consensus on Polymarket heavily favors 29°C (44.5% implied probability) as the highest temperature in São Paulo on April 18, driven by the latest forecasts from Brazil's National Institute of Meteorology (INMET) and Climatempo, projecting daytime highs of 28–30°C under clear skies and a subtropical high-pressure ridge promoting solar heating with low humidity around 50–60%. Recent observations on April 17 showed highs near 30°C amid lingering summer warmth—0.34°C above historical norms per INMET's summer recap—positioning 30°C (19%) and 28°C (17%) as strong contenders if minor cloud cover or sea breezes intervene. April climatology typically sees highs of 24–27°C on the Saffir-Simpson-irrelevant scale here, but this warm anomaly sustains elevated odds; extremes like 34°C+ (<1%) remain unlikely absent unusual advection. Updated model runs expected overnight could refine these probabilities ahead of official station measurements at Congonhas Airport.
This market will resolve to the temperature range that contains the highest temperature recorded at the Sao Paulo-Guarulhos International Airport Station in degrees Celsius on 18 Apr '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Sao Paulo-Guarulhos International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/br/guarulhos/SBGR.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$11,887End Date
Apr 18, 2026Market Opened
Apr 16, 2026, 12:26 AM ETResolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Trader consensus on Polymarket heavily favors 29°C (44.5% implied probability) as the highest temperature in São Paulo on April 18, driven by the latest forecasts from Brazil's National Institute of Meteorology (INMET) and Climatempo, projecting daytime highs of 28–30°C under clear skies and a subtropical high-pressure ridge promoting solar heating with low humidity around 50–60%. Recent observations on April 17 showed highs near 30°C amid lingering summer warmth—0.34°C above historical norms per INMET's summer recap—positioning 30°C (19%) and 28°C (17%) as strong contenders if minor cloud cover or sea breezes intervene. April climatology typically sees highs of 24–27°C on the Saffir-Simpson-irrelevant scale here, but this warm anomaly sustains elevated odds; extremes like 34°C+ (<1%) remain unlikely absent unusual advection. Updated model runs expected overnight could refine these probabilities ahead of official station measurements at Congonhas Airport.
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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