Highest temperature in Seoul on June 30?

Platform comparison

Market context

The highest temperature recorded at Incheon International Airport on 30 June 2026 will determine the outcome of this prediction market, with the current crowd-implied probability of a "YES" resolution sitting at 0%. This contract trades on Polymarket using USDC on the Polygon network, where conditional tokens reflect the market’s stark confidence that the temperature will fall outside the specific range being wagered upon.

Historically, Seoul’s June highs climb from 77°F to 81°F, rarely exceeding 87°F, yet the nation has witnessed record-breaking heatwaves that shatter these norms, including a 41.0°C peak in Hongcheon and a 39.6°C surge in Seoul itself in 2018[2][6]. Recent data confirms a trend of intensifying summer warmth, with South Korea recording its hottest average June temperature since 1973 last year and 59 cities seeing record-breaking heat in July 2025[4][7]. These precedents suggest that while the 0% probability aligns with typical averages, the underlying climate volatility could render the current pricing fragile if an extreme anomaly occurs.

Traders must monitor real-time Wunderground data for Incheon and watch for any sudden shifts in regional weather patterns, as the resolution depends entirely on the highest temperature recorded at any time on that day[2]. The forecast for Seoul in June 2026 indicates daily highs ranging from 85°F to 91°F, with an average high of 88°F, which may already be factored into the market’s low probability assessment[8]. Any official announcements from the Korea Meteorological Administration regarding heat advisories or unexpected cloud cover changes could act as immediate catalysts, potentially altering the on-chain pricing dynamics before the settlement window closes on 30 June 2026 at 12:00 UTC.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on June 30? 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 PolyGram. 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.