Highest temperature in Seoul on July 8?

Platform comparison

Market context

The underlying event is the highest temperature recorded at Incheon International Airport on 8 July 2026, with the market currently pricing a 0% chance for the YES outcome. Historical July baselines in Seoul typically hover between 25–30°C, with occasional peaks nudging 30°C, while trader consensus on similar contracts often favours the 27–28°C range due to short-range model uncertainty[1][3]. A notable outlier occurred in early July when Seoul reached 37.7°C, the highest reading in 117 years, suggesting that while extreme heat is possible, the current 0% probability likely reflects a lack of immediate forecast signals for such a spike[8].

Traders should monitor the Korea Meteorological Administration’s short-range forecasts for any sudden shifts in temperature or humidity, as these directly influence the “feels like” metric and potential record highs[5]. The settlement relies on Wunderground data, meaning any discrepancies in station reporting or timing could alter the resolution, so watching exchange spot prices and funding rates for BTC and ETH may provide indirect macro cues if weather-driven volatility impacts broader crypto sentiment[2]. Recent news from Anadolu Ajansı highlights that South Korea has already recorded unprecedented July temperatures, reinforcing the need to track real-time weather updates closely as the settlement window approaches[8].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

Can I use Bitcoin directly?

No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.

How volatile are crypto prediction markets?

Crypto markets react to spot prices — a 5% BTC move typically shifts a "BTC above X by date" market 10-20%. Polymarket crypto market liquidity is usually six-figure USD, sufficient for active trading.

Are crypto prediction markets taxable in the US?

In the US, prediction market gains are typically treated as ordinary income or short-term capital gains depending on holding period. Consult a tax professional for your specific situation — we cannot provide tax advice.