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 and resolved against historical weather data from Wunderground. The settlement window closes at 12:00 UTC on that date, locking in the highest temperature recorded across all times during the calendar day. Current crowd pricing at 0% YES suggests traders are either awaiting clarity on which temperature bracket the market offers or have not yet engaged with this specific weather derivative.

July temperatures in Seoul historically cluster between 28–32°C, with extreme heat occasionally pushing toward 35°C during particularly intense heat waves. The 2018 heat wave saw Seoul reach 39.6°C, whilst more typical late-July peaks range from 29–31°C. Incheon Airport Station, located on reclaimed land near the coast, typically records slightly cooler readings than central Seoul due to maritime influence, which should anchor expectations toward the lower end of summer extremes. This geographic distinction matters for settlement accuracy, as the resolution source is explicitly tied to airport station data rather than city centre measurements.

The East Asian monsoon pattern and any tropical cyclone activity in late July 2026 will be the primary catalysts shaping temperature outcomes. The Korean Meteorological Administration publishes seasonal forecasts and weekly outlooks that traders can cross-reference; any issued heat wave warnings or unusual atmospheric pressure systems in the weeks preceding 28 July would signal elevated temperature risk. Current USDC settlement mechanics mean traders locking positions now face two months of weather model uncertainty, with forecast confidence typically improving only 10–14 days before the event date.

Methodology

This page reads Highest temperature in Seoul on July 28? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed alongside for venue context. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

How does UMA secure the resolution?

The UMA Optimistic Oracle uses a bond system: a proposer posts a bond, a two-hour challenge window opens. On dispute the losing side forfeits the bond — financial incentive for honest resolution.

How volatile are crypto prediction markets?

Crypto markets react to spot prices — a 5% BTC move typically shifts a "BTC above X by date" market 10-20%. Polymarket crypto market liquidity is usually six-figure USD, sufficient for active trading.