Highest temperature in Busan on August 15?

Platform comparison

Market context

On 15 August 2026, the highest temperature recorded at Gimhae International Airport in Busan will determine this market's settlement. The resolution hinges on data from Weather Underground's Daily Observations table rather than summary figures, a distinction that occasionally produces meaningful variance in recorded extremes. The settlement window closes at midday UTC, capturing the full diurnal cycle through early morning.

Busan's August climate presents a narrow historical band for extreme heat. Daily maxima in mid-August typically range between 28–32°C, with the city's coastal position moderating temperatures relative to inland South Korean regions. The 0% crowd-implied probability suggests traders are pricing near or below the lower quartile of historical August 15th outcomes, implying either conservative positioning or expectations of cooler-than-typical conditions. Comparable markets on Korean summer temperatures have shown prediction-market probabilities tracking within 2–3 percentage points of meteorological consensus when settlement approaches.

Tropical cyclone activity across the Western Pacific in early-to-mid August 2026 will merit monitoring, as such systems can suppress temperatures substantially or, conversely, drive humidity-inflated heat indices. The Korea Meteorological Administration typically issues seasonal outlooks in late July; their August 2026 forecast will provide the nearest official guidance on regional temperature anomalies. Sea surface temperatures in the Korea Strait and any established monsoon patterns by mid-month will function as leading indicators for the final reading.

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

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 Best Prediction Markets 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.

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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What are the best prediction markets for UK traders in 2026?

For UKGC-regulated markets: Betfair Exchange (sports, politics) and Smarkets (sports, politics, lower commission than Betfair). For broader global event prediction: Polymarket (deepest liquidity, 0% fee, USDC settlement). For US-regulated option: Kalshi (USD, limited UK payment options). Most serious UK traders use a combination of Betfair for regulated sports and Polymarket for broader markets.