Highest temperature in Seoul on July 28?

Platform comparison

Market context

Seoul's peak temperature on 28 July 2026 will be measured at Incheon International Airport Station, with the market currently pricing all temperature ranges at zero probability. This represents an unusual state for a weather market on a specific future date, suggesting either minimal trading activity or an expectation that settlement data will be unavailable.

Historical records show Seoul experiences its most intense heat in late July, with average highs around 29–30°C and frequent spikes above 32°C during summer heat waves. The 2018 heat wave saw temperatures exceed 39°C across the region; more recently, July 2023 brought sustained peaks near 33–35°C. Incheon Airport, located on the coast, typically records slightly cooler readings than central Seoul due to maritime influence, though the differential rarely exceeds 2–3°C. The zero probability across all ranges suggests traders may be waiting for clearer seasonal forecasts or questioning data availability rather than genuinely expecting no temperature reading.

Traders should monitor South Korean meteorological agency forecasts released in early July 2026, which will clarify whether a typical summer pattern or anomalous conditions are expected. The settlement depends entirely on Wunderground's historical records for Incheon; any gaps in that data source could complicate resolution. Given late July's consistent heat profile in the region, ranges in the 30–35°C band have historically been most frequent, though the current flat probability distribution suggests the market lacks conviction or liquidity to establish meaningful odds.

Methodology

We track Highest temperature in Seoul on July 28? 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

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.

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 Who Will Win trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.