Highest temperature in Seoul on June 29?

Platform comparison

Market context

Seoul on 29 June 2026 will see its peak temperature recorded at Incheon International Airport, with the market resolving to the Celsius range containing that daily high. The crowd currently prices a YES outcome at 19%, implying traders expect the temperature to fall below the threshold defining that range.

Historically, June in Seoul is warm but not extreme, with typical highs between 19°C and 28°C, though recent data shows a maximum of 34.0°C recorded on 19 June 2026[1][6]. The average high for June is 29°C (84°F), while July averages slightly cooler at 29°C (85°F) but with higher volatility[2][5]. Given that the monsoon season typically begins late June, the 19% probability likely reflects uncertainty about whether a heat spike will occur before the rains intensify, rather than a baseline expectation of extreme heat[1].

Traders should monitor the Korea Meteorological Administration’s short-range forecasts for any sudden temperature surges ahead of 29 June, as elevated sea surface temperatures have driven record warmth in recent months[3][10]. The settlement depends entirely on Wunderground’s hourly data for Incheon Airport, so any gaps or delays in that feed could affect resolution clarity[1]. With the settlement window closing at 12:00 UTC on 29 June, the on-chain conditional tokens on Polygon (settled in USDC) will lock in the final price based on the verified temperature range[1].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 Kalshi 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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

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