Highest temperature in Seoul (Incheon) on August 12?

Platform comparison

Market context

Seoul's Incheon International Airport will record a daily high temperature on 12 August 2026, measured at the official meteorological station and logged in Weather Underground's Daily Observations table. The market currently prices all temperature ranges at 0% on Polygon, suggesting either insufficient liquidity or that traders are awaiting clearer seasonal forecasting data before committing USDC to conditional tokens. This is typical for weather markets settling nearly two years forward, where historical patterns matter more than current atmospheric conditions.

Seoul experiences peak summer heat in August, with historical daily highs typically ranging from 28–32°C at Incheon during mid-month. The 0% crowd probability reflects the inherent difficulty in pricing a specific temperature range for a date eighteen months away rather than scepticism about whether heat will occur. Comparable August days at Incheon show clustering around 29–31°C, though extreme heat events pushing above 33°C have occurred in recent summers, particularly during heat dome episodes. The resolution mechanism's reliance on Weather Underground's Daily Observations table—rather than the Day High & Low summary—introduces a technical specification that traders must verify against historical discrepancies between the two data sources.

Traders monitoring this contract should track South Korean meteorological agency forecasts as summer 2026 approaches and watch for any El Niño or La Niña patterns that influence East Asian heat distribution. Seasonal outlooks typically become more reliable three to six months before the target date. The settlement window closes at 12:00 UTC on 12 August, creating a narrow window for final price discovery once actual conditions emerge.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

UK Frequently Asked Questions

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.

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%.