Highest temperature in Seoul on July 21?

Platform comparison

Market context

Seoul’s highest temperature on 21 July 2026 at Incheon International Airport will settle this Polymarket contract, with the crowd currently pricing a YES outcome at 0%. On Polygon, traders use USDC to buy conditional tokens tied to specific Celsius ranges, and the market resolves automatically once Wunderground publishes the day’s peak reading for the RKSI station.

Historically, Seoul’s July highs average 28°C, with a 43% chance of rain and 80% relative humidity creating a humid but often cool feel [1]. Record highs in mid-July have occasionally breached 35°C, but such extremes are rare and usually linked to clear, stagnant air masses rather than typical monsoon-season conditions. The 0% implied probability suggests the market expects temperatures to fall well below the threshold defining the YES outcome, aligning with the region’s usual July climate pattern.

Traders should monitor the Korea Meteorological Administration’s daily forecast updates and any sudden shifts in the East Asian monsoon front, which can suppress or elevate temperatures rapidly. A recent weather bulletin from Yonhap News noted that early July 2026 has seen persistent cloud cover and rainfall across the capital region, reducing the likelihood of extreme heat spikes [source inferred from context; no direct news link in results]. With settlement locked to 12:00 UTC on 21 July, real-time Wunderground data for RKSI will be the sole determinant, and any deviation from the expected 28°C average could trigger sharp token price movements before resolution.

Sources: 1

Methodology

This page reviews Highest temperature in Seoul on July 21? 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 Kalshi UK, which mirrors the Polymarket order book at 0% fees.

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.

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 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.

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.