TOTAL VOLUME:
$134b
24H VOL:
$107,351,958
24H TRANSACTIONS:
2,388,728,490
OPEN INTEREST:
$1,416,970,024
400,720
Markets across
30,097
events
MATCHED EVENTS:
2,633
PLATFORM COVERAGE:
5
Polymarket:
39%
VS.
Kalshi:
61%
Closed: Jun 28, 8:00 AM EST
Polymarket
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 28 Jun '26. The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Sao Paulo-Guarulhos International Airport Station, 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 until the first data point for the following date has been published on the resolution source. 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. Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
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 28 Jun '26. The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Sao Paulo-Guarulhos International Airport Station, 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 until the first data point for the following date has been published on the resolution source. 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. Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Prediction market odds often diverge from traditional weather analyst forecasts because they incorporate real-time trader behavior and financial incentives. While meteorologists issue deterministic point forecasts or confidence intervals based on atmospheric models, this market aggregates the views of participants who have money at stake. Traders may price in tail risks, seasonal patterns, or local microclimatic factors that analysts downweight. Comparing the implied probability from market odds to the confidence level in official weather forecasts can reveal where the crowd sees asymmetric risk or where consensus is strongest.
On Polymarket, traders set prices by buying and selling shares that represent different temperature ranges or outcomes. On Polymarket, prices reflect that venue's order book, liquidity, and how traders price the outcome right now. The market uses an automated market maker (AMM) model, so prices adjust dynamically based on order flow and liquidity. Each outcome's price reflects the collective belief of all participants about the likelihood of that temperature occurring. As new information emerges—updated weather models, seasonal data, or real-time conditions—traders adjust their positions, causing prices to move and the implied probability to shift accordingly.
This market resolves around Jun 28, 2026, once June 28 has passed and the highest temperature recorded in São Paulo that day is verified. The outcome is confirmed against credible public sources reporting the actual peak temperature. Traders who correctly predicted the temperature range or threshold win their shares at full value, while incorrect positions expire worthless. Resolution typically occurs within hours or a day after the event, once official meteorological data is published and confirmed.
Updated weather models and seasonal forecasts are primary drivers of price movement in this market. Major atmospheric patterns—such as cold fronts, heat waves, or unusual pressure systems affecting Brazil—can shift trader expectations significantly. Real-time temperature readings in the days leading up to June 28 provide concrete data that narrows uncertainty. Climate anomalies, El Niño or La Niña conditions, and even local urban heat island effects discussed in meteorological reports can influence positioning. As the date approaches, actual daily highs in São Paulo will anchor expectations more tightly around the final outcome range.