Highest temperature in Seoul (Incheon) on August 16?

Platform comparison

Market context

Seoul's summer temperatures in mid-August typically peak between 28–32°C, though the city's urban heat island effect and proximity to Incheon International Airport—situated on reclaimed land with limited vegetation—can push readings higher. The resolution mechanism here requires traders to reference Weather Underground's Daily Observations table rather than the summary high-low figures, a distinction that matters when automated systems scrape weather data; discrepancies between granular observation records and rounded daily summaries occur frequently enough to warrant programmatic verification of the exact source field before settlement.

Historical August data from Incheon shows that temperatures above 33°C occur in roughly 30–40% of years during mid-month, whilst readings exceeding 35°C remain relatively uncommon but not unprecedented. The 0% crowd probability suggests either a market formation issue or traders anchoring to cooler-than-typical forecasts. Monitoring Korea Meteorological Administration advisories and real-time station feeds becomes essential; traders building conditional orders should establish triggers tied to 10-day forecast updates rather than relying on static seasonal baselines.

The settlement window closes at midday UTC on 16 August 2026, creating a narrow window for final data verification. Traders implementing automated resolution checks should account for potential reporting delays at the Incheon station and cross-reference against backup sources, since Weather Underground occasionally experiences synchronisation lags with official Korean meteorological records. Building a scraper that polls the Daily Observations table directly rather than relying on API summaries reduces settlement risk substantially.

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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Polymarket Review UK. 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.

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%.