Highest temperature in Seoul on July 8?

Platform comparison

Market context

Seoul is currently experiencing a sharp heat spike, with temperatures surging well above the seasonal norm as the monsoon rains have temporarily stalled. In the last 24 hours, the city reached 37.8°C, shattering the previous record for early July and setting a new benchmark for the 1–10 period since records began[1]. This extreme warmth, combined with stifling humidity that pushes the felt temperature over 34°C, creates a volatile environment where a single clear day could push readings into the highest historical bracket[5].

Historical data frames the current 0% YES probability as a misreading of the current thermal trajectory. While July typically averages 28.9°C with frequent rain, the 1939 record of 36.8°C was broken just yesterday, proving that the ceiling for extreme heat is actively rising[1][9]. The 2026 forecast suggests daily highs can reach 94°F (34.4°C), and with the monsoon season often extending to late July, a sudden break in cloud cover could trigger a rapid temperature climb similar to the 1939 anomaly[2][5].

Traders must monitor the Korea Meteorological Administration’s short-range forecasts for any shift from rain to clear skies, as this is the primary catalyst for a heat spike[7]. The immediate dependency is the persistence of the current high-pressure system; if the rain probability drops below 60% and winds shift from the south to the southeast, temperatures could surge rapidly[7]. Recent reports confirm that central inland cities like Seoul are the wettest, meaning a sudden cessation of rain is the critical trigger needed to break the 37°C threshold again[5].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on July 8? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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.

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 Prediction Today 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.