Highest temperature in Seoul (Incheon) on August 5?

Platform comparison

Market context

Seoul’s late-summer heat is the main driver here, but the contract resolves on the *highest* temperature at Incheon Intl Airport Station, so the key question is whether the airport site tracks the city’s peak or runs a little cooler onshore. Local reporting says a severe heatwave warning has been issued for the Seoul metropolitan area and that Seoul is expected to reach 38°C today, with intense heat persisting day and night in the west of the country.[1] That makes a 0% YES price look like an obvious disconnect with the weather backdrop, although the exact outcome still depends on the airport station’s own daily maximum on Wunderground rather than a city-wide reading.[15]

For comparison, August is normally a very hot month in Seoul, with average highs around 28°C to 31°C and occasional spikes well into the upper 30s, including a recorded August record high of 38.2°C cited by Holiday Weather.[16] That historical range matters because a market framed around the day’s maximum should not be read like a “will it be hot?” question; it is more about whether the station clears whatever bucket boundaries the market uses. On broader exchange platforms, the same weather view is priced differently: Polymarket shows direct implied probabilities, while Kalshi and Betfair/Smarkets present decimal-style pricing, so the same underlying view can look numerically different even when the trade is equivalent. Fee treatment also diverges, with exchange-style books typically charging commission on winnings and Kalshi/Polymarket using their own market fees and settlement rules, while access and KYC can be more restrictive outside their core jurisdictions.

The immediate catalysts are the day’s actual temperature path and any rain or coastal cloud cover that clips the afternoon high. SBS says showers may affect parts of the western regions today, but also that inland areas are generally clear for now, which favours strong solar heating if the airport stays out of any shower band.[1] Traders should watch the Korea Meteorological Administration’s short-range forecasts and the Wunderground daily history page itself, because this market settles on the observed station maximum rather than a forecasted city high.[4][15]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Seoul (Incheon) on August 5? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Robinhood Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). On-chain settlement clears in minutes — the fastest payout path of the four.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Robinhood Prediction Markets has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Robinhood Prediction Markets offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.