Highest temperature in Seoul on July 28?

Platform comparison

Market context

Seoul's highest temperature on 28 July 2026 will be measured at Incheon International Airport Station and settled against Wunderground's historical records. The market currently prices this outcome at 0% across all temperature bands, reflecting settlement mechanics where traders select conditional tokens representing specific Celsius ranges rather than a binary outcome. On Polygon, USDC collateral backs these positions, with resolution determined by the single highest reading recorded throughout that calendar day at the designated weather station.

Historical July temperatures in Seoul cluster between 28–33°C for daily highs, though extreme heat events occasionally push readings above 35°C. The summer of 2023 saw Seoul experience multiple days exceeding 33°C, whilst 2022 recorded a peak of 39.6°C during an exceptional heat wave. These precedents suggest the market's current zero probability across all bands reflects either technical pricing constraints or genuine uncertainty about which specific range will capture the day's maximum. Traders should examine whether the market has properly distributed probability mass or if certain temperature brackets remain mispriced relative to climatological norms for late July.

The Korea Meteorological Administration publishes seasonal forecasts and heat advisories typically 10–14 days ahead of significant weather events. Traders should monitor whether any heat dome patterns develop over East Asia in mid-July 2026, as these systems frequently drive Seoul temperatures into the 34–37°C range. Wunderground's historical data feed updates daily, and settlement will depend entirely on the station's recorded maximum, making instrument calibration and data integrity the final arbiter of outcomes.

Methodology

We track Highest temperature in Seoul on July 28? 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 Kalshi UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

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