Highest temperature in Seoul (Incheon) on August 10?

Platform comparison

Market context

Seoul is trading as a **hot-weather favourite**, but the market’s current **0% YES** pricing makes it a near-total underdog on the listed contract bands. The practical question for traders is not whether it will be warm — it usually is in August — but whether the official Incheon Airport reading on the day lands in a narrow bucket around the consensus zone, rather than drifting into an outside range. August climatology for Seoul points to persistent heat and humidity, with average highs around the high 20s to low 30s Celsius, while current guidance has been running much hotter than normal.[8][10][18]

Recent comparable cases argue against treating this as a benign summer-weather toss-up. Reuters reported South Korea’s heatwave intensifying in early August, with Seoul forecast as high as 39C and the country posting multiple record or near-record readings, including 41.4C nationally on 31 July and Seoul-year highs above 36C.[7][11][14][15] That backdrop supports the crowd leaning towards a warm outcome rather than a cool one, but it also explains why the value, if any, is more likely in contrarian lower-temperature bins if cloud cover, sea-breeze effects, or shower activity limit the daytime peak below expectations.[2][3]

For catalysts, the key inputs are the Korea Meteorological Administration short-range forecast updates and any late-shifting observation trend from nearby stations, because the market resolves off the highest temperature in Weather Underground’s Daily Observations table, not the headline day-high summary.[2][4] Traders should watch for cloud thickening, easterly flow changes, and any rainfall risk that could suppress insolation; Polymarket’s own market page currently shows the consensus clustered around the mid-30s Celsius, with 34C and 33C the leading outcomes.[2]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul (Incheon) on August 10? 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

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 Who Will Win 2026. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Who Will Win 2026 trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.