Highest temperature in Seoul on June 20?

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Active sub-markets

Market context

On 20 June 2026, Seoul will experience early summer conditions with daytime highs typically ranging from 19°C to 28°C, well below the extreme thresholds that would trigger a “YES” outcome in this prediction market. The current crowd-implied probability of 2% for a YES reflects the market’s recognition that such high temperatures are historically improbable for this date, as June in South Korea remains comfortably warm but far from the intense heat of midsummer.

Historical data shows that the average warmest day in Seoul during June reaches only 28.06°C, with most days staying between 22°C and 27°C[1][9]. Even in late June, when humidity and rain increase, temperatures rarely exceed 30°C, making a settlement above the highest range highly unlikely. This aligns with the 2% probability, as traders correctly price in the low likelihood of record-breaking heat before the monsoon season fully begins[3][4].

Traders should monitor the Korea Meteorological Administration’s short-range forecasts, updated daily at 18:00, for any anomalies in temperature or humidity that could shift expectations[6]. While no major heatwave announcements are currently issued, the onset of the monsoon season from late June to mid-July may bring sudden weather shifts that could influence on-chain conditional token pricing[1][4]. With USDC and Polygon underpinning Polymarket’s mechanics, liquidity will respond swiftly to any forecast updates, but the fundamental weather pattern remains stable.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Seoul on June 20? 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

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

Where can I trade this market with the lowest fees?

On Polymarket 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 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.

What does it cost to trade on Polymarket UK?

Zero. Polymarket UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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.