Highest temperature in Seoul on July 3?

Platform comparison

Market context

Seoul’s July 2026 weather is dominated by the monsoon season, with daily highs typically reaching 25–30°C and humidity pushing “feels like” temperatures above 34°C during midday[1][2]. The Incheon International Airport Station, where this market resolves, sits in a coastal zone that often experiences slightly cooler peaks than central Seoul but remains subject to the same humid, rain-interrupted heat patterns[1]. Historical data shows Seoul recorded 37.1°C on 8 July 2008—the highest July temperature since 1908—while recent forecasts for July 2026 project highs between 81° and 91°F (27–33°C)[3][6]. Given this context, the crowd-implied 0% probability for a specific high-temperature range appears inconsistent with the region’s known volatility, suggesting either a mispriced range or a misunderstanding of the settlement criteria.

Traders should monitor the Korea Meteorological Administration’s short-range forecasts and Wunderground’s daily updates for Incheon, as sudden shifts in cloud cover or rain intensity can rapidly alter peak temperatures[4]. The Sinchon Water Gun Festival in late July may increase local humidity and cooling effects, indirectly affecting temperature readings[1]. Meteorologists have warned that South Korea’s 2026 summer could be its hottest yet, with heatwaves arriving earlier than usual[6][7]. On platforms like Polymarket, implied probabilities are shown as decimals (e.g., 0.00), whereas Kalshi and Betfair use fractional or decimal odds, creating divergent risk perceptions for the same event. Fee structures also vary: Polymarket charges no platform fees but has gas costs, while Kalshi imposes trading fees and requires KYC, limiting access for international users. These structural differences mean the same 0% probability may reflect different liquidity conditions or trader confidence across platforms.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Seoul on July 3? 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

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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

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. 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.