Highest temperature in Seoul (Incheon) on August 10?

Platform comparison

Market context

The latest shift in the last 24–48 hours is that forecasters have kept Seoul’s early-August heat signal elevated, with official-style outlooks clustering around a daytime high near 34°C and other services still calling for a hot, humid day with little rain relief. That leaves the market’s 0% implied probability for **YES** hard to reconcile with the weather setup, because a single-topping daily maximum at Incheon can easily land in the low-to-mid 30s on an August heat day. [1][13][15]

Recent history also argues against treating this as a low-temperature outcome by default. Seoul just came through an exceptional heat spell, including a 39.6°C reading at the city level on 1 August, while KMA-linked reporting has shown multiple Korean locations pushing above 40°C in the same broader heatwave pattern. Even allowing for Incheon Airport being cooler than inner-city Seoul, August climatology and recent extremes suggest the relevant contest is usually between the 32–35°C bands rather than a mild summer ceiling. [7][12][14]

For traders, the key catalysts are the day’s evolving observation data, not the summary high/low line: this market resolves from Weather Underground’s **Daily Observations** table for Incheon Intl Airport Station, and revisions remain relevant until the first datapoint for the following date appears. Intraday cloud cover, sea-breeze effects, and any late-afternoon temperature spike will matter more than morning conditions, while the main external reference points are the KMA-style forecast updates and any revision to the local high if heat persists longer than expected. [1]

Sources: 1 · 2 · 3 · 4 · 5

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

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

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%.