Highest temperature in Seoul on July 3?

Platform comparison

Market context

The underlying real-world event is straightforward: on 3 July 2026, what will be the highest temperature recorded at Incheon International Airport, measured in degrees Celsius? This market resolves to the temperature bracket containing that daily maximum, sourced from Wunderground’s official history for the Incheon Intl Airport Station.

Historically, Seoul’s July highs cluster between 25–30°C, with occasional peaks nudging 30°C or higher, though humidity often pushes the “feels like” temperature above 34°C[2][3]. The 30°C bracket recently surged 41% in implied probability on a similar July 1 contract, landing at 69.5% before resolution[1]. Yet meteorologists warn this summer could be South Korea’s hottest yet, with Seoul hitting 37.1°C on 8 July 2008—the highest July reading since 1908[8]. This context explains why the current 0% YES probability for the highest bracket is not a dismissal of heat, but a reflection of extreme uncertainty and bracket specificity.

Traders should monitor the monsoon schedule (Jangma), which typically runs from late June to mid-July, bringing concentrated heavy rainfalls that can suppress daytime highs[2]. Recent forecasts predict record heat and torrential rains for Korea this summer, with temperatures rising 2–3 weeks earlier than last year[7]. Watch for daily updates from the Korea Meteorological Administration on precipitation probability and wind patterns, as short, intense rain windows of 60–90 minutes can rapidly cool the air[3]. On-chain, the contract trades in USDC on Polygon using conditional tokens; price movements will hinge on whether the monsoon delays or intensifies, directly affecting the likelihood of extreme heat on 3 July.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seoul on July 3? 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 PolyGram, 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 PolyGram. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.