Highest temperature in Seoul on July 8?

Platform comparison

Market context

On 8 July 2026, the Incheon International Airport Station will record its highest temperature for the day, a single data point that determines the outcome of a prediction market resolving to a specific Celsius range. The current crowd-implied probability of 0% for the "YES" outcome suggests the market believes the temperature will not hit the threshold in question, likely 26°C, which is unusually low given historical patterns. This probability must be read against the backdrop of an extreme heatwave currently gripping South Korea, where Seoul reached 37.1°C on 7 July—the highest July temperature since national data collection began in 1908, with nearby cities like Gwangmyeong and Paju hitting 40°C [1].

Historically, July in Seoul typically sees daytime highs between 25–30°C, with an average midday reference of 27°C, making a 26°C threshold statistically probable rather than anomalous [2]. The 0% probability appears disconnected from recent records, including the 37.7°C peak in early July 2025, the highest in 117 years [7], and the all-time Korean record of 41.0°C set in Hongcheon [9]. A programmatically approaching trader would script a bot to pull real-time Wunderground data for the Incheon station, comparing it against the 26°C threshold, while flagging the current heatwave advisories upgraded to warnings across the country as a critical dependency [1].

Traders should monitor the ongoing heatwave warnings and meteorological forecasts indicating temperatures could soar beyond 40°C, as these are the primary catalysts for the market outcome [1]. The settlement window ends at 12:00 UTC on 8 July, requiring precise timing for data ingestion, and any sudden shift in weather patterns, such as rain or cloud cover, would alter the temperature trajectory. Recent reports confirm South Korea is on track for one of the most intense summer heatwaves in recorded history, with meteorologists warning of sustained highs [1], making the 0% probability a potential mispricing that a conditional order strategy could exploit if the temperature data confirms the heatwave’s persistence.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on July 8? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 Polymarket Bot UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Polymarket Bot UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.