Highest temperature in Seoul on July 18?

Platform comparison

Market context

The settlement hinges on the highest temperature recorded at Incheon International Airport on 18 July 2026, measured in Celsius and resolved via Wunderground's historical weather data. Seoul's mid-July climate sits firmly within the East Asian summer monsoon season, when daily highs routinely exceed 30°C. The 0% implied probability across all temperature ranges suggests either a technical issue with market setup or an expectation that no valid settlement data will be available—a material concern given the resolution dependency on a specific weather station's historical record being accessible and complete on the settlement date.

Historical July temperatures at Incheon Airport provide the baseline for calibration. Over the past decade, mid-July highs have ranged between 28°C and 34°C, with 32°C representing a typical peak for the period. Extreme heat events pushing above 35°C occur but remain infrequent; the station recorded 36.4°C in July 2018 during an exceptional heatwave. The current crowd probability of zero across all bins is inverted from typical weather market behaviour and warrants scrutiny of whether traders are pricing in data availability risk rather than temperature uncertainty.

Traders should monitor South Korea's meteorological forecasts from late June onwards, particularly any alerts from the Korea Meteorological Administration regarding heat waves or unusual atmospheric patterns. The monsoon's intensity and timing directly influence whether mid-July conditions track toward seasonal norms or extremes. Confirmation that Wunderground's historical archive will remain accessible through the settlement window is essential; any platform changes or data gaps would create resolution ambiguity.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Who Will Win 2026, which mirrors the Polymarket order book directly.

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 Who Will Win 2026. 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.

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.

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.