Highest temperature in Seoul on July 17?

Platform comparison

Market context

Seoul faces its peak summer heat on 17 July 2026, with the Incheon International Airport station expected to record the day’s highest temperature in degrees Celsius. On Polymarket, this event is priced as a USDC conditional token contract on Polygon, where the crowd currently assigns a 0% probability to the “YES” outcome for any specific high-temperature range, despite the frontrunner being 31°C at 76% and 32°C or higher at 22% [1]. This apparent contradiction suggests the market is treating the binary “YES” label as a misaligned or unresolved condition, while the underlying temperature distribution remains actively traded across multiple ranges.

Historically, mid-July in Seoul sees daily highs between 28°C and 34°C, with 31°C being the most frequent peak in the last decade. Comparable cases from 2023 and 2024 show that temperatures exceeding 32°C occur roughly 20–25% of the time, aligning closely with the current 22% probability for “32°C or higher” [1]. The 0% crowd-implied probability for the binary outcome likely reflects a technical framing issue rather than a belief that extreme heat is impossible, as the temperature-range market clearly anticipates significant warmth.

Traders should monitor the Korea Meteorological Administration’s daily forecast releases at 09:00 KST and real-time updates from Wunderground, the official resolution source, which will log the highest temperature for RKSI at any time on 17 July. A sudden shift in monsoon activity or a heat dome announcement from the East Asian weather centre could rapidly alter the distribution, pushing the 32°C+ probability higher. No official announcements have yet been made for 17 July, but the seasonal pattern suggests heat is the baseline expectation.

Sources: 1

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

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 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'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.