Official observations from Brazil's Instituto Nacional de Meteorologia (INMET) confirm a maximum temperature of 30°C at key São Paulo stations on April 18, driving trader consensus to 100% market-implied probability for that outcome as the definitive resolution data. This aligns with prevailing dry autumn conditions under subtropical high pressure, where numerical weather prediction models like those from CPTEC/INPE had forecasted highs near 30°C in the days prior, with minimal convective activity to push temperatures higher. While daily maxima measurements carry high reliability from calibrated sensors, rare post hoc revisions during quality control or discrepancies across secondary stations (e.g., Congonhas vs. Guarulhos airports) could theoretically alter positioning, though no such issues have surfaced in initial reports.
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?
30°C 100.0%
24°C or below <1%
25°C <1%
26°C <1%
$81,319 Vol.
$81,319 Vol.
Apr 18, 2026
24°C or below
No
25°C
No
26°C
No
27°C
No
28°C
No
29°C
No
30°C
Yes
31°C
No
32°C
No
33°C
No
34°C or higher
No
30°C 100.0%
24°C or below <1%
25°C <1%
26°C <1%
$81,319 Vol.
$81,319 Vol.
Apr 18, 2026
24°C or below
$3,313 Vol.
No
25°C
$3,754 Vol.
No
26°C
$9,161 Vol.
No
27°C
$11,952 Vol.
No
28°C
$12,783 Vol.
No
29°C
$8,289 Vol.
No
30°C
$16,069 Vol.
Yes
31°C
$8,589 Vol.
No
32°C
$2,898 Vol.
No
33°C
$1,795 Vol.
No
34°C or higher
$2,717 Vol.
No
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.Official observations from Brazil's Instituto Nacional de Meteorologia (INMET) confirm a maximum temperature of 30°C at key São Paulo stations on April 18, driving trader consensus to 100% market-implied probability for that outcome as the definitive resolution data. This aligns with prevailing dry autumn conditions under subtropical high pressure, where numerical weather prediction models like those from CPTEC/INPE had forecasted highs near 30°C in the days prior, with minimal convective activity to push temperatures higher. While daily maxima measurements carry high reliability from calibrated sensors, rare post hoc revisions during quality control or discrepancies across secondary stations (e.g., Congonhas vs. Guarulhos airports) could theoretically alter positioning, though no such issues have surfaced in initial reports.
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
$81,319End Date
Apr 18, 2026Market Opened
Apr 16, 2026, 12:26 AM ETResolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
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.Official observations from Brazil's Instituto Nacional de Meteorologia (INMET) confirm a maximum temperature of 30°C at key São Paulo stations on April 18, driving trader consensus to 100% market-implied probability for that outcome as the definitive resolution data. This aligns with prevailing dry autumn conditions under subtropical high pressure, where numerical weather prediction models like those from CPTEC/INPE had forecasted highs near 30°C in the days prior, with minimal convective activity to push temperatures higher. While daily maxima measurements carry high reliability from calibrated sensors, rare post hoc revisions during quality control or discrepancies across secondary stations (e.g., Congonhas vs. Guarulhos airports) could theoretically alter positioning, though no such issues have surfaced in initial reports.
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
$81,319End Date
Apr 18, 2026Market Opened
Apr 16, 2026, 12:26 AM ETResolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Official observations from Brazil's Instituto Nacional de Meteorologia (INMET) confirm a maximum temperature of 30°C at key São Paulo stations on April 18, driving trader consensus to 100% market-implied probability for that outcome as the definitive resolution data. This aligns with prevailing dry autumn conditions under subtropical high pressure, where numerical weather prediction models like those from CPTEC/INPE had forecasted highs near 30°C in the days prior, with minimal convective activity to push temperatures higher. While daily maxima measurements carry high reliability from calibrated sensors, rare post hoc revisions during quality control or discrepancies across secondary stations (e.g., Congonhas vs. Guarulhos airports) could theoretically alter positioning, though no such issues have surfaced in initial reports.
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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