Highest temperature in Seoul on July 9?

Platform comparison

Market context

Seoul is bracing for peak summer heat on 9 July 2026, with meteorological records indicating the city’s highest early-July temperature ever reached 37.8°C just one day prior. This real-world event sets the stage for a prediction market where the crowd-implied probability of a “YES” outcome sits at 0%, suggesting traders believe the temperature will not fall into the specified range, despite the extreme heat already observed.

Historically, July in Seoul is the hottest and most humid month, with average highs climbing to 30°C and feels-like temperatures exceeding 34°C due to humidity above 80%. Record-breaking heat has become increasingly common; in 2026 alone, Seoul hit 37.7°C, the highest early-July reading in 117 years of data since 1908, while South Korea overall recorded its highest-ever July temperatures [5][8]. These precedents frame the current 0% probability as a stark divergence from analyst consensus, which typically anticipates temperatures well within the upper range during this period.

Traders should monitor real-time updates from the Korea Meteorological Administration and Wunderground, the official resolution source, for any sudden shifts in precipitation or cloud cover that could suppress temperatures. Recent forecasts indicate slight rainfall with a 60% probability of precipitation, which may act as a cooling catalyst [3]. The Straitstimes reported the 37.8°C peak on 8 July, underscoring how volatile early-July heat can be and why the 0% market line may reflect overconfidence in a cooling trend rather than a true assessment of risk [5].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seoul on July 9? 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.