Highest temperature in Seoul on July 27?

Platform comparison

Market context

The event is whether the highest temperature recorded at Incheon International Airport Station reaches a particular Celsius band on 27 July 2026. In this market, a **YES** share pays out if the day’s peak temperature at that station falls inside the specified range; a **NO** share pays if it does not. The settlement source is Wunderground’s daily history page for RKSI, so the relevant figure is the single highest reading for the whole day, not an average or the temperature in Seoul city centre.

A current crowd-implied probability of **0% YES** signals that traders are effectively pricing in an outcome outside the target range. That is unusual for a late-July Korean weather market, because July is typically Seoul’s warmest and rainiest month, with warm, humid conditions common and daytime highs often around 30°C[1][3]. Recent coverage also pointed to nationwide heatwave warnings, with Seoul forecast around 26–33°C and showers in the capital region, which is the sort of set-up that can still produce a wide spread between morning rain-cooled air and a higher afternoon maximum[2].

For traders, the main catalysts are the day’s local forecast, the timing of any showers, and whether cloud cover or sea-breeze effects limit the airport’s peak reading. The market uses Incheon International Airport Station rather than a broader Seoul metric, so small station-specific differences matter. Hour-by-hour updates around the settlement window are therefore more relevant than broad seasonal averages, especially if rain arrives early and suppresses the maximum before midday[2][3].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

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.