Highest temperature in Seoul on June 20?

Platform comparison

Active sub-markets

Market context

On 20 June 2026, Seoul will experience early summer conditions with daytime highs typically ranging from 19 to 28°C, as the monsoon season begins to approach but has not yet intensified. The market resolves on the highest temperature recorded at Incheon International Airport, with the crowd currently assigning a 14% implied probability to a specific outcome, suggesting traders view extreme heat as unlikely given the season’s moderate baseline.

Historical data shows that the average warmest day in Seoul during June reaches approximately 26.7°C, with early June often feeling like an extended spring and late June becoming noticeably hotter and more humid [1][3]. This frames the current 14% probability as a cautious bet against a temperature spike, since June’s heat remains manageable compared to July and August, and humidity has not yet reached exhausting levels [1]. Traders should monitor the Korea Meteorological Administration’s short-range forecasts for any sudden shifts in cloud cover or shower patterns, as afternoon showers are common and can suppress peak temperatures [2][4]. Recent travel guidance also highlights that rainfall increases toward the end of the month, with moderate to high averages of 135mm, which could further limit temperature extremes [2].

When comparing platforms like Polymarket, Kalshi, and Betfair, key divergences emerge in how odds are presented—decimal odds versus implied probability—and in fee structures, KYC requirements, and liquidity depth. For this specific market, platforms offering decimal odds may provide clearer risk-reward calculations, while those with lower fees and broader KYC reach could attract more retail participation, influencing the final settlement price.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Seoul on June 20? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). Kalshi Alternative UK routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

FAQ

Where can I trade this market with the lowest fees?

On Kalshi Alternative 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?

Kalshi Alternative 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 does it cost to trade on Kalshi Alternative UK?

Zero. Kalshi Alternative 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 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.