Highest temperature in Seoul (Incheon) on August 17?

Platform comparison

Market context

On 17 August 2026, Seoul's Incheon International Airport will record a daily high temperature in Celsius. This market asks traders to predict which temperature band that reading will fall into. In prediction markets, a YES share pays out if the outcome occurs; a NO share pays out if it doesn't. Here, traders select a specific temperature range—say, 28–30°C—and hold YES shares if they believe the actual high will land there, or NO shares if they expect it elsewhere. The market's settlement hinges on Weather Underground's Daily Observations table for Incheon station, not the summary figures, making precision in data sourcing critical.

Seoul experiences peak summer heat in mid-August, with historical August highs typically ranging from 28–32°C. The current 0% probability assigned to YES suggests the crowd either expects an outcome outside the specified range or reflects minimal trading activity at present. August 2026 forecasting remains uncertain at this distance, though seasonal patterns offer a baseline: Incheon's August average high sits around 29°C, with extreme heat events pushing toward 33–35°C during particularly intense heat waves. The 2018 Korean heat wave, for instance, saw Seoul record 39.6°C in early August, demonstrating the potential for outlier conditions.

Traders should monitor long-range weather models as August 2026 approaches, particularly forecasts issued in late July that typically gain reliability within two weeks of the target date. Pacific typhoon activity and the strength of the North Pacific High pressure system will shape whether conditions remain near seasonal norms or trend toward exceptional heat. Any official heat-wave warnings from Korea Meteorological Administration in the days preceding 17 August would signal material shifts in expected temperatures.

Methodology

We track Highest temperature in Seoul (Incheon) on August 17? 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.

UK Frequently Asked Questions

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 Prediction Market UK. 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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.