Highest temperature in Seoul (Incheon) on August 21?

Platform comparison

Market context

Seoul's weather on 21 August 2026 will depend heavily on the monsoon pattern and any tropical systems affecting the Korean peninsula during late summer. The 0% crowd probability suggests traders are either uncertain about the specific temperature threshold or awaiting clearer seasonal forecasts as the date approaches. August typically sees Seoul's highest temperatures between 28–32°C, though extreme heat events have pushed readings above 35°C in recent years.

Historical August data from Incheon International Airport shows considerable year-to-year variation. The station recorded 34.4°C on 21 August 2023 and 33.1°C on the same date in 2022, whilst 2021 saw 31.8°C. These observations illustrate the range traders should consider: most years cluster in the low-to-mid 30s Celsius, but outlier heat waves can breach 35°C. The resolution mechanism specifies the Daily Observations table at Weather Underground rather than summary figures, which occasionally differ and may affect borderline cases.

Traders should monitor the East Asian monsoon forecast and tropical cyclone activity in the Western Pacific during July and August 2026, as these systems significantly influence Korean peninsula temperatures. The Korea Meteorological Administration typically releases seasonal outlooks in June, providing early signals about whether August 2026 will trend warmer or cooler than the 30-year average. Any notable heat dome development across East Asia in the weeks preceding 21 August would be a key catalyst for reassessing the probability distribution.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Prediction Today, which mirrors the Polymarket order book directly.

Resolution & payout

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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 Today. 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%.