Highest temperature in Seoul on June 29?

Platform comparison

Market context

On 29 June 2026, traders are assessing whether Incheon International Airport will record a peak temperature exceeding the threshold that defines a “high” day in Seoul, with current crowd-implied probability at 18% for a YES outcome. This real-world event hinges on whether June’s typical warming trend—where daily highs climb from 77°F to 81°F—will be interrupted by an anomalous heat spike, as has occurred in recent years.

Historically, Seoul has seen extreme June heat, including a record-breaking 39.6°C in 2018 and a new all-time national high of 41.0°C in Hongcheon in 2023. In 2025, 59 South Korean cities recorded record June temperatures, with 30 June marking the hottest June day since 1904. These precedents suggest that while 18% may appear low, the region’s volatility in recent summers means such probabilities can shift rapidly if atmospheric conditions align.

Traders should monitor the Korea Meteorological Administration’s daily forecasts and any sudden shifts in the East Asian monsoon pattern, which can trigger rapid temperature increases. A recent Chosun Ilbo report (1 July 2025) highlighted how unseasonal heatwaves have become more frequent, with 30 June 2025 reaching 35.8°C—the highest June temperature ever recorded. Watch for official announcements on heatwave advisories and satellite data indicating low-pressure systems moving toward the capital region, as these are key catalysts for temperature surges.

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Methodology

We track Highest temperature in Seoul on June 29? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Best Prediction Markets UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.