Official Instituto Nacional de Meteorologia (INMET) observations from the Mirante de Santana station—the authoritative source for São Paulo city temperatures—confirm the highest temperature on May 13 reached exactly 25°C, driving trader consensus to near-certainty at 100% implied probability. This positioning reflects the lingering influence of a polar air mass that brought record lows earlier in the week (9.4°C on May 11), with cloudy skies and high humidity capping diurnal warming despite slight recovery from prior days' 21.7°C maximum. Hourly data shows a midday peak consistent with forecast model ensembles predicting mid-20s highs under overcast conditions. Scenarios challenging this include rare post hoc data revisions from instrument calibration or if resolution hinges on an alternate station like Guarulhos Airport showing divergence, though INMET precedence makes shifts improbable.
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 May 13?
Highest temperature in Sao Paulo on May 13?
25°C 100.0%
26°C <1%
27°C <1%
28°C <1%
$49,598 Vol.
$49,598 Vol.
25°C
100%
26°C
<1%
27°C
<1%
28°C
<1%
29°C
<1%
30°C
<1%
31°C
<1%
32°C or higher
<1%
25°C 100.0%
26°C <1%
27°C <1%
28°C <1%
$49,598 Vol.
$49,598 Vol.
25°C
100%
26°C
<1%
27°C
<1%
28°C
<1%
29°C
<1%
30°C
<1%
31°C
<1%
32°C or higher
<1%
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: May 11, 2026, 12:09 AM ET
Resolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...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...Official Instituto Nacional de Meteorologia (INMET) observations from the Mirante de Santana station—the authoritative source for São Paulo city temperatures—confirm the highest temperature on May 13 reached exactly 25°C, driving trader consensus to near-certainty at 100% implied probability. This positioning reflects the lingering influence of a polar air mass that brought record lows earlier in the week (9.4°C on May 11), with cloudy skies and high humidity capping diurnal warming despite slight recovery from prior days' 21.7°C maximum. Hourly data shows a midday peak consistent with forecast model ensembles predicting mid-20s highs under overcast conditions. Scenarios challenging this include rare post hoc data revisions from instrument calibration or if resolution hinges on an alternate station like Guarulhos Airport showing divergence, though INMET precedence makes shifts improbable.
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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