Highest temperature in Seoul (Incheon) on August 3?

Platform comparison

Market context

Polymarket is pricing this Incheon Airport temperature contract at **0% YES**, which means the market is currently assigning no odds to the highest reading on 3 August landing in the specified settlement range. On Polymarket, that price sits on-chain in **USDC** on **Polygon**, with traders exchanging **conditional tokens** against the Wunderground-based final observation for Incheon Intl Airport Station.

The read-through from comparable summer setups is straightforward: Seoul and the capital area are already under a heatwave warning, with forecasts calling for Seoul to reach around **37°C** and Incheon about **34°C** today, while national coverage also points to widespread tropical nights and strong sunshine. [1][3][8] That leaves the key distinction for this market in the airport observation itself, which can undercut metropolitan forecasts if sea breeze, cloud cover, or local marine influence hold the station a few degrees lower than inland readings. Historical August context also matters: Seoul’s August highs usually sit in the mid-20s to low-30s Celsius, but early-August heat spikes are common enough that a zero price mainly reflects the need for a very specific station-level outcome rather than a denial of hot weather overall. [2][17][18]

The main catalysts are the Korea Meteorological Administration short-range updates, any shifts in the eastward wind pattern mentioned in local reporting, and whether showers remain confined to southern or inland areas rather than spilling into the capital region. [1][4][8] For a Polymarket trader, the practical watchlist is the intraday trajectory at Incheon Airport: morning cloud, afternoon clearing, and any sea-breeze suppression can all cap the day’s high below Seoul’s inland forecast, while a hotter, drier afternoon would push the reading up quickly. Current forecast services still show a wide spread in Seoul-area expectations, which is why the exact station source and settlement window matter more than broad city weather headlines. [2][11][14]

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.

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 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.

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.