Highest temperature in Seoul on July 31?

Platform comparison

Market context

The real-world event here is the day’s **highest temperature at Incheon International Airport Station**, which is the figure the market source will use for 31 July 2026. In a prediction market, a **YES** share pays out if the event happens as defined, while a **NO** share pays out if it does not; here, that means the final observed daily maximum must fall into the specified Celsius range when Wunderground publishes the station record.

A **0% YES** implied probability usually means the crowd sees the targeted temperature band as effectively out of reach, often because the band is very hot, very cold, or both compared with the forecast and seasonal baseline. That framing matters because late July in Seoul is normally warm and humid, but not every extreme is common: recent forecast services show Seoul around the low-to-mid 30s Celsius for the day, while July averages are typically much lower, with highs around the mid-to-upper 20s Celsius. WeatherSpark also notes that 31 July is among the clearer days of the month, which can matter because sunshine raises the chance of a stronger afternoon maximum.[1][2][11][13]

For traders, the main catalysts are the short-term forecast updates, not policy or event announcements: changes in cloud cover, rain timing, wind direction, and humidity can quickly shift the day’s peak temperature. SBS reported that South Korea was under persistent heat, with Seoul forecast near 34°C and clear weather expected to continue through the following week, which supports an elevated maximum but does not guarantee a specific band.[2] Because the market resolves from the airport station rather than central Seoul, the key dependency is whether Incheon Airport’s own observation ends up a degree or two cooler or warmer than city forecasts suggest.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seoul on July 31? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Prediction Market UK, which mirrors the Polymarket order book at 0% fees.

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.

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 Prediction Market 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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Market 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.