Highest temperature in Hong Kong on June 23?

Platform comparison

Active sub-markets

Market context

Hong Kong is bracing for its hottest day of the year so far, with temperatures already soaring past 34.6°C and hail warnings issued as the city swelters under extreme heat[7]. This real-world intensity frames the current Polymarket pricing, where the contract for a June 23, 2026 peak above 35°C sits at a 0% YES probability despite the immediate weather crisis. On-chain, USDC trades on Polygon using conditional tokens, yet the market remains frozen on the abstract date, ignoring the tangible heatwave unfolding today.

Historical June data shows daily highs typically ranging from 30°C to 34.6°C, with the 2026 average forecasted near 30°C[6][7]. While AccuWeather projects daily highs between 88°F and 93°F (roughly 31°C to 34°C), the Hong Kong Observatory’s seasonal outlook warns of above-normal temperatures for June through August[1][4]. The 0% probability likely reflects the statistical rarity of exceeding 35°C on a specific date, even as the 2026 tropical cyclone season, starting in June, could disrupt typical heat patterns[2].

Traders must monitor the Hong Kong Observatory’s “Daily Extract” for the finalized “Absolute Daily Max” once published, as the market cannot resolve until this data is official[5]. Recent warnings of extreme heat hitting 37°C in the New Territories underscore the volatility traders should watch for in upcoming announcements[5]. The settlement window ends 2026-06-23T12:00:00Z, making the timing of the Observatory’s data release the critical catalyst for any shift in conditional token valuations.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on June 23? 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 Kalshi 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.

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.

What does it cost to trade on Kalshi UK?

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

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Kalshi UK triggers a quick verification flow that finishes in minutes.