Ensemble weather models from INMET and international sources like ECMWF and GFS drive the tight race between 30°C (39%) and 31°C (31%) for Sao Paulo's highest temperature on March 22, with ensemble means hovering around 30.5°C amid a transitioning El Niño pattern favoring above-normal autumn warmth. Differentiating factors include forecast cloud cover—partial afternoon sunshine could push peaks to 31°C via enhanced insolation, while increased humidity or sea breeze incursions might cap at 30°C—compounded by urban heat island effects amplifying city readings by 1-2°C over rural stations. Historical March highs average 28-29°C, but recent runs show low-probability tails for 32°C+ if subsidence strengthens, explaining trailing odds. Traders eye tomorrow's 12Z updates for resolution shifts.
Experimental AI-generated summary referencing Polymarket data · UpdatedHighest temperature in Sao Paulo on March 22?
Highest temperature in Sao Paulo on March 22?
30°C 40%
31°C 31%
29°C 15%
32°C 11%
$14,337 Vol.
$14,337 Vol.
24°C or below
<1%
25°C
<1%
26°C
<1%
27°C
<1%
28°C
3%
29°C
15%
30°C
40%
31°C
31%
32°C
11%
33°C
2%
34°C or higher
<1%
30°C 40%
31°C 31%
29°C 15%
32°C 11%
$14,337 Vol.
$14,337 Vol.
24°C or below
<1%
25°C
<1%
26°C
<1%
27°C
<1%
28°C
3%
29°C
15%
30°C
40%
31°C
31%
32°C
11%
33°C
2%
34°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: Mar 18, 2026, 6:02 AM ET
Resolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Resolution Source
https://www.wunderground.com/history/daily/br/guarulhos/SBGRResolver
0x69c47De9D...Ensemble weather models from INMET and international sources like ECMWF and GFS drive the tight race between 30°C (39%) and 31°C (31%) for Sao Paulo's highest temperature on March 22, with ensemble means hovering around 30.5°C amid a transitioning El Niño pattern favoring above-normal autumn warmth. Differentiating factors include forecast cloud cover—partial afternoon sunshine could push peaks to 31°C via enhanced insolation, while increased humidity or sea breeze incursions might cap at 30°C—compounded by urban heat island effects amplifying city readings by 1-2°C over rural stations. Historical March highs average 28-29°C, but recent runs show low-probability tails for 32°C+ if subsidence strengthens, explaining trailing odds. Traders eye tomorrow's 12Z updates for resolution shifts.
Experimental AI-generated summary referencing Polymarket data · Updated
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