Highest temperature in Hong Kong on June 30?

Platform comparison

Market context

The real-world event hinges on whether Hong Kong’s peak temperature on 30 June 2026 reaches or exceeds 32°C, the threshold that currently carries a 26% crowd-implied probability of a YES outcome. On Polymarket, this contract is priced in USDC on the Polygon network, where conditional tokens reflect trader sentiment that 32°C is the frontrunner at 60%, with 31°C a close second at 28%[1]. The market will resolve only once the Hong Kong Observatory finalises its “Absolute Daily Max (deg. C)” in the official Daily Extract, a dependency that locks settlement until data publication[1].

Historical June data frames this probability: the highest monthly mean maximum temperature in Hong Kong’s June records was 32.4°C in 2016, followed by 32.3°C in 2015, while recent extremes have surged past 34°C and even 35.6°C in the year’s hottest days so far[5][6]. The average June high sits around 31°C, but overcast conditions and humid summer air frequently push peaks higher, making 32°C a plausible but not dominant outcome[3][7]. Traders should weigh whether this year’s heatwave pattern, which already delivered 35.6°C, will sustain or taper by late June.

Key catalysts include the Hong Kong Observatory’s scheduled extreme heat warnings and daily temperature bulletins, which often precede record spikes[8]. A recent SCMP report noted the Observatory warned of extreme heat as temperatures hit 34.4°C in Tsim Sha Tsui, underscoring the volatility traders must monitor[10]. Settlement depends entirely on the Observatory’s finalised Daily Extract, meaning no on-chain resolution occurs until that official source is published[1]. Watch for updates on the Observatory’s website and SCMP’s weather coverage for real-time shifts in probability.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Hong Kong on June 30? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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'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 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.