Highest temperature in Seoul (Incheon) on August 1?

Platform comparison

Market context

At Incheon Intl Airport, the settlement key is the *single highest hourly/observed temperature* recorded on 1 August, so the relevant question for a trader is not the day’s average but whether the airport station prints an unusually hot spike before noon UTC. The crowd’s 0% YES pricing suggests the market is effectively treating an extreme upper tail event as the only path to settlement, which is consistent with a meteorological venue that usually sits several degrees below Seoul’s inland extremes because of coastal moderation and airport exposure.

For historical framing, August is one of the warmest months in the Seoul/Incheon area, with Seoul’s August climate normals around 29–31°C daytime highs, but the record set in the capital reached 39.6°C on 1 August 2018 during a nationwide heatwave[1][12][17]. Recent reporting on 1 August 2026 showed the peninsula already starting hot, with Incheon’s minimum at 26.8°C and Seoul’s at 27.4°C before midday, which matters because a high overnight base can make a modest daytime rise sufficient to move the final range[2]. For programmatic monitoring, a bot would typically poll the Wunderground history page, normalise the station’s Celsius output, and compare the day’s maximum against the market’s range buckets rather than relying on forecasts alone.

The catalysts to watch are the Korea Meteorological Administration’s short-range and medium-range updates, plus any heatwave advisories, because those are the inputs most likely to shift intraday expectations for airport maxima[15][16]. If the KMA maintains hot, humid conditions into the afternoon, a trader model would weight the upper ranges more heavily; if marine influence or cloud cover caps the temperature, the distribution compresses towards the lower buckets. A practical workflow is to run conditional orders around forecast revisions and to refresh the settlement feed after each new observation cycle, since the market resolves from the recorded station maximum rather than from the forecast peak.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul (Incheon) on August 1? 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'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.