Highest temperature in Seoul on July 20?

Platform comparison

Market context

Seoul’s peak summer heat on 20 July 2026 hinges on conditions at Incheon International Airport, where the day’s highest temperature will determine the market outcome. Historical July data shows typical highs around 28°C, with precipitation chances near 43%, meaning cloud cover and rain often suppress extreme temperatures [1]. The current 0% YES implied probability suggests the crowd expects the temperature to fall outside the specific range offered, likely because recent patterns or forecasts point to milder conditions than the threshold requires.

Comparable July days in Seoul frequently see temperatures between 25°C and 30°C, rarely breaching 35°C unless a strong heatwave coincides with low humidity and minimal cloud [1]. Traders should monitor real-time updates from Wunderground for the Incheon station, as the market resolves solely on that source’s recorded maximum. No major weather announcements are scheduled for 20 July, but sudden shifts in the East Asian monsoon or unexpected clear-sky conditions could act as catalysts. Given the wettest-month status of July, sustained rainfall remains the most probable dampener on extreme heat, aligning with the crowd’s bearish stance.

Sources: 1

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 Best Prediction Markets UK, which mirrors the Polymarket order book directly.

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

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.

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 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.