Highest temperature in Seoul on July 11?

Platform comparison

Market context

Seoul faces its peak summer heat on 11 July 2026, with the Incheon International Airport station expected to record a daily high between 27°C and 35°C. Historical data shows July highs in Seoul typically range from 27°C to 31°C, rarely exceeding 35°C, while recent years have seen record-breaking heatwaves pushing temperatures above 39°C in surrounding regions [2][4][6]. The current crowd-implied probability of 0% for any specific outcome suggests the market is either mispriced or awaiting clearer signals, contrasting sharply with Polymarket’s frontrunner at 31°C (37% probability) and Kalshi’s implied odds favouring 30–32°C ranges [1][10].

Traders should monitor the Korea Meteorological Administration’s daily 06:00 UTC forecast updates and Wunderground’s real-time station data for Incheon, as humidity and rain could suppress temperatures below 30°C despite seasonal trends [4][9]. A recent heatwave in August 2025, which made July 2025 South Korea’s second-hottest since 1973, indicates that extreme heat is increasingly probable, though localised cloud cover or precipitation on 11 July could alter outcomes [7]. The divergence between Polymarket’s 31°C consensus and the 0% implied probability on this contract highlights a potential arbitrage opportunity, especially if forecast models shift toward higher temperatures ahead of settlement.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on July 11? 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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 PolyGram. 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram 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.