Highest temperature in Seoul on July 27?

Platform comparison

Market context

Seoul’s daytime high on 27 July will be shaped by a warm, unsettled summer pattern rather than a steady heat spike, with South Korean reporting on Monday’s outlook calling for showers in the capital region and forecast highs of 26–33°C in Seoul itself.[1] For this market, the key settlement source is the *Incheon Intl Airport Station* daily maximum on Wunderground, so the relevant trade is not the city headline but the single highest reading recorded there before the window closes.[1]

That makes the current crowd-implied **0% YES** easier to read in context: it is consistent with a market that is either extremely cautious about the event clearing the relevant temperature band, or treating the contract as mispriced because the resolution point is a specific airport station rather than a broader Seoul weather station. July climatology in Seoul normally centres around highs near 30°C, but with frequent rain and humidity-driven swings rather than a persistent extreme.[2][3] On Polymarket, that probability is shown directly; on Kalshi it would be framed through contract prices and tick movements; on Betfair and Smarkets, traders would compare back/lay decimal odds after exchange commission, with KYC access often narrower on some venues than others.

For catalysts, traders should watch the final hourly evolution of convection and rainfall over the capital region, since cloud cover and showers can suppress the day’s maximum even when the broader air mass is hot.[1] The main dependency is the actual Wunderground history entry at Incheon airport, not a forecast headline, so late-morning to early-afternoon conditions matter most for whether the station’s maximum lands in the target temperature range.[1]

Sources: 1 · 2 · 3

Methodology

This page compares Highest temperature in Seoul on July 27? 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 Kalshi Alternative, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

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.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Kalshi Alternative 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.