Highest temperature in Seoul on July 11?

Platform comparison

Market context

Seoul faces a July 11 daytime high likely near 30–32 °C, with the Incheon International Airport station expected to record the day’s peak temperature under moisture-laden southwesterly flow and scattered showers. The prediction market for this event currently shows a 0% implied probability for any outcome resolving below 30 °C, while Polymarket’s leading outcome is 31 °C at 37%, followed closely by 32 °C at 33% and 30 °C at 30% [1]. This tight clustering around the 30–32 °C range reflects collective trader confidence that early-July maxima will stay within historical norms of 25–30 °C, though recent variability introduces a roughly two-degree spread across model runs [1].

Historical precedents frame this probability: South Korea recorded its second-hottest July since 1973 in 2025, with an average of 27.1 °C, and Seoul itself hit 37.7 °C in early July 2025—the highest such reading in 117 years [6][7]. While all-time national records reached 41.0 °C in Hongcheon in 2023, Seoul’s typical July highs rarely exceed 32 °C, rarely falling below 25 °C [2][4]. Traders should monitor the Korea Meteorological Administration’s weekly heat forecasts and any announcements on tropical night persistence, as the KMA has projected above-average temperatures through early August with no significant rainfall [5]. A recent Chosun Ilbo report noted heat wave alerts raised to “severe” levels six days earlier than the previous year, underscoring the catalyst of early-season intensity [5].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi vs Polymarket, which mirrors the Polymarket order book directly.

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

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

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.

Do I need to KYC for this market?

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