Highest temperature in Seoul on May 28?

Platform comparison

Active sub-markets

Market context

On 28 May 2026, the highest temperature recorded at Incheon International Airport Station will fall into one of several defined ranges, measured in degrees Celsius. The settlement hinges on historical weather data from Wunderground, which archives daily temperature extremes for this major Seoul-area weather station. The 0% crowd probability suggests traders currently perceive no meaningful likelihood of an extreme heat outcome, though the specific threshold range triggering that assessment remains unspecified in the market terms.

Seoul's May temperatures historically cluster between 20–28°C, with occasional spikes into the low 30s during heat waves. The current zero probability reading may reflect either a narrow resolution band set at an improbable extreme, or simply low trader participation at market launch. Comparable Korean spring weather markets have typically resolved within expected seasonal ranges; May 2025 saw Seoul peak at 29.4°C, whilst May 2024 reached 31.2°C on its warmest day. These precedents establish that mid-to-high 20s outcomes are routine, whilst 32°C+ readings occur but remain less frequent.

Traders should monitor the Korea Meteorological Administration's May forecasts and any announced weather patterns from late April onwards. El Niño or La Niña conditions, if active, could shift seasonal norms. The settlement window closes at 12:00 UTC on 28 May, meaning final temperature readings must be confirmed by Wunderground within hours of the calendar day's end. Any data discrepancies between Wunderground and KMA records could delay or complicate resolution, though the market explicitly designates Wunderground as the sole authoritative source.

Methodology

We track Highest temperature in Seoul on May 28? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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

Where can I trade this market with the lowest fees?

On Polymarket Tax UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket Tax UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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 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.