Highest temperature in Seoul on July 4?

Platform comparison

Market context

Seoul’s early July highs typically cluster between 27°C and 31°C, with the North Pacific high-pressure system driving hot, humid conditions that can occasionally reach 35°C. Historical data from the Korea Meteorological Administration shows that July 4 falls within this genuinely wide temperature window, where no single bracket commands majority support. In comparable markets, the 29°C range has traded at roughly 30.5% implied probability, reflecting a one-in-three chance it hits exactly that mark, while the NO side remains favoured at 66–70% because six other brackets share the remaining probability. This 0% YES crowd-implied probability for the current market suggests traders view the 29°C outcome as highly unlikely, possibly due to anomalous cooling signals or a shift in the historical baseline.

A power-user approaching this programmatically would monitor real-time Wunderground feeds for the Incheon Intl Airport Station, cross-referencing with Korea Meteorological Administration alerts for tropical night streaks, which recently broke a century-old record with 22 consecutive nights above 25°C in Seoul. Traders should watch the scheduled release of July 2025 climate summaries, which noted South Korea’s second-hottest July since 1973, averaging 27.1°C, and the Anadolu Ajansı report confirming Seoul reached 37.7°C—the highest early July temperature in 117 years. These catalysts indicate that while extreme heat is possible, the market’s 0% YES stance may reflect a mispricing of volatility, as the resolution window ends at noon KST on July 4, 2026, leaving little time for late-day temperature spikes to alter the outcome.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on July 4? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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.

FAQ

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 Bot UK. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Bot UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.