Highest temperature in Seoul on July 28?

Platform comparison

Market context

Seoul's peak temperature on 28 July 2026 will be recorded at Incheon International Airport Station and measured in Celsius. The Polymarket contract currently prices this event at 0% YES, meaning traders are assigning negligible probability to whichever temperature range this particular market resolves to—likely an extreme upper or lower bound that sits outside historical norms for that date. Settlement hinges on Wunderground's historical weather data for that specific station, with the resolution window closing at midday UTC on the settlement date itself.

July temperatures in Seoul cluster consistently between 28–32°C as daily highs, with occasional spikes to 34–35°C during heat waves. The city's 30-year average high for late July sits around 29°C, though the record high for any July day reaches 39.6°C (set in 2018). Current 0% pricing suggests the market is testing an outlier threshold—either an unusually cold peak (below 20°C) or an extreme heat scenario (above 37°C) that defies typical summer patterns. Historical volatility in Korean summer weather remains material; the 2022 and 2023 monsoon seasons brought cooler-than-average peaks, whilst 2018 saw sustained heat records.

Traders monitoring this contract should track seasonal forecasts from the Korea Meteorological Administration and broader East Asian pressure systems as July 2026 approaches. The East Asian summer monsoon's strength and timing will be the primary driver of whether Seoul experiences typical seasonal heat or anomalous conditions. Any significant La Niña or El Niño signal emerging in early 2026 could shift probabilities, as these patterns influence regional temperature regimes months in advance.

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.

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 PolyGram. 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.

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.

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.