Highest temperature in Seoul on July 3?

Platform comparison

Market context

The real-world event in question is the highest temperature recorded at Incheon International Airport on 3 July 2026, which will determine the outcome of a prediction market where the crowd currently assigns zero probability to a “YES” result. This implies the market believes the temperature will fall outside the specific range being bet on, despite Seoul’s historical tendency for intense early-July heat.

Historically, early July in Seoul regularly sees highs between 32°C and 35°C, with 37.7°C recorded in 2018 as the highest early-July temperature in 117 years of records[4][7]. The region’s average daily high in July climbs from 81°F to 85°F (27.2°C to 29.4°C), rarely dropping below 74°F (23.3°C)[1]. South Korea also set an all-time national heat record of 41.0°C in Hongcheon in 2025, indicating a broader trend of escalating summer extremes[2]. These comparable cases suggest that a zero probability is unusually low unless the market range is set far above plausible highs.

Traders should monitor the Korea Meteorological Administration’s daily forecasts and Wunderground’s real-time updates for Incheon, as sudden shifts in cloud cover or monsoon activity could alter temperatures significantly[3]. Recent reports note that South Korea endured its second-hottest July since 1973, with an average of 27.1°C, reinforcing the likelihood of elevated temperatures[3]. No major weather announcements are scheduled, but dependencies include the timing of the East Asian monsoon and any unexpected heatwave advisories. The settlement window ends 12:00 UTC on 3 July 2026, so last-minute data will be critical.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seoul on July 3? 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 Best Prediction Markets UK, which mirrors the Polymarket order book at 0% fees.

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

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.

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.