Official observations from São Paulo-Guarulhos International Airport (GRU), the market's resolution source, and corroborating Instituto Nacional de Meteorologia (INMET) stations recorded a maximum air temperature of 27°C on April 13, solidifying trader consensus at near 100% implied probability. Partly cloudy skies, sea breeze influences, and moderate humidity capped daytime heating after a cool morning low around 16°C, aligning with pre-event forecast model consensus from INMET and Centro de Gerenciamento de Emergências (CGE) projecting highs of 26–28°C. This positioning reflects verified hourly METAR data showing no exceedance, consistent with April climatological averages near 26°C. A realistic challenge would require post hoc data revision from quality control or a discrepant reading from secondary stations like IAG-USP, though such adjustments are rare for established peaks; final INMET bulletin expected soon.
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 13?
27°C 100.0%
18°C or below <1%
19°C <1%
20°C <1%
$96,941 Vol.
$96,941 Vol.
18°C or below
No
19°C
No
20°C
No
21°C
No
22°C
No
23°C
No
24°C
No
25°C
No
26°C
No
27°C
Yes
28°C or higher
No
27°C 100.0%
18°C or below <1%
19°C <1%
20°C <1%
$96,941 Vol.
$96,941 Vol.
18°C or below
No
19°C
No
20°C
No
21°C
No
22°C
No
23°C
No
24°C
No
25°C
No
26°C
No
27°C
Yes
28°C or higher
No
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 9, 2026, 12:08 AM ET
Resolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
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.
Resolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Official observations from São Paulo-Guarulhos International Airport (GRU), the market's resolution source, and corroborating Instituto Nacional de Meteorologia (INMET) stations recorded a maximum air temperature of 27°C on April 13, solidifying trader consensus at near 100% implied probability. Partly cloudy skies, sea breeze influences, and moderate humidity capped daytime heating after a cool morning low around 16°C, aligning with pre-event forecast model consensus from INMET and Centro de Gerenciamento de Emergências (CGE) projecting highs of 26–28°C. This positioning reflects verified hourly METAR data showing no exceedance, consistent with April climatological averages near 26°C. A realistic challenge would require post hoc data revision from quality control or a discrepant reading from secondary stations like IAG-USP, though such adjustments are rare for established peaks; final INMET bulletin expected soon.
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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