Highest temperature in Seoul on July 20?

Platform comparison

Market context

On 20 July 2026, meteorologists will record the peak temperature at Incheon International Airport, the official proxy for Seoul’s heat, to settle this prediction market. A YES share wins if the highest temperature falls within a specific range defined by the market, while a NO share wins if it falls outside that range; traders buy these shares based on their forecast of the actual weather outcome.

The current 0% crowd-implied probability for a YES outcome likely signals a mismatch between the market’s temperature threshold and Incheon’s historical July climatology, rather than an actual impossibility of high heat. In July, South Korea experiences hot, humid conditions with daily average highs nearing 30°C, often feeling like over 34°C due to humidity exceeding 80% [2]. Historical data shows July is the rainiest month during the monsoon season, yet peak temperatures frequently reach 27°C or higher, making a 0% probability for any reasonable high-temperature range inconsistent with typical seasonal patterns [1].

Traders should monitor real-time updates from Wunderground, the designated resolution source, which logs the highest temperature recorded for all times on 20 July at the Incheon station. While no specific weather announcements are scheduled for this future date, the market’s settlement depends entirely on this single data point, meaning any deviation from the expected 27°C frontrunner could shift probabilities instantly [1]. The market closes at 12:00 UTC on 20 July 2026, so participants must watch for live temperature feeds as the day progresses, as humidity and rainfall intensity can cause rapid fluctuations in peak readings [2].

Sources: 1 · 2 · 3

Methodology

This page reviews Highest temperature in Seoul on July 20? 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 Prediction Market UK, which mirrors the Polymarket order book at 0% fees.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

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.