Highest temperature in Seoul (Incheon) on August 18?

Platform comparison

Market context

Seoul's weather on 18 August 2026 will determine the settlement of this temperature-range contract, with resolution tied to the highest reading recorded at Incheon International Airport's meteorological station. The market currently shows 0% implied probability across all temperature bands, suggesting either insufficient liquidity or a data-loading issue rather than genuine consensus that no temperature will be recorded.

Seoul experiences peak summer heat in mid-August, with historical daily maxima typically ranging between 28°C and 33°C during this period. The city's 30-year August average high sits around 29.4°C, though extreme readings above 35°C have occurred in roughly one-in-five years. The 2018 heat wave pushed temperatures to 39.6°C in Seoul proper, whilst Incheon—situated on the coast with moderating maritime influence—generally records 1–2°C lower peaks than central Seoul. Current crowd pricing at zero across all bands diverges sharply from historical frequency distributions and suggests the market has not yet attracted substantive trading activity or faces technical settlement specification concerns.

Traders should monitor Korea Meteorological Administration forecasts released in early August 2026, particularly any alerts regarding heat domes or high-pressure systems tracking over the peninsula. The resolution methodology's explicit reliance on Weather Underground's Daily Observations table rather than summary figures creates a dependency on data accuracy at a single source; discrepancies between platforms have occasionally triggered disputes in weather-derivative markets. Seasonal patterns favour temperatures in the 28–32°C range, though the specific resolution bands available will determine whether current zero-probability readings reflect genuine market indifference or structural liquidity constraints.

Methodology

We track Highest temperature in Seoul (Incheon) on August 18? 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 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.

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