Highest temperature in Hong Kong on June 30?

Platform comparison

Market context

The real-world event hinges on whether Hong Kong’s highest temperature on 30 June 2026 reaches the threshold implied by the 95% YES probability, specifically within the range defined by the Hong Kong Observatory’s daily maximum record. Historically, June maxima in Hong Kong typically span 29°C to 34°C, with the highest monthly mean maximum recorded at 32.4°C in 2016[7][8]. Recent data shows this year’s June highs fluctuating between 86°F and 91°F (roughly 30°C to 33°C), while the absolute daily maximum so far hit 35.6°C earlier in the month[1][9]. This context suggests the 95% probability is plausible only if the threshold sits near the lower end of the typical range, as extreme outliers above 34°C are less common in late June despite recent heat spikes.

Traders approaching this market programmatically should monitor the Hong Kong Observatory’s “Daily Extract” updates, which finalise the absolute daily max once data is published[3]. A key catalyst is the forecasted nine-day rain period starting this weekend, expected to drop temperatures to 26–30°C and potentially suppress the 30 June peak[2]. The Observatory has already warned of squally thunderstorms and hail peaking Sunday–Monday, which could further cool conditions by Tuesday[2]. For conditional order strategies, dependencies include the timing of the Daily Extract release and any sudden shifts in synoptic conditions, such as the low-pressure trough lingering over southern China[2]. Recent news confirms the heat is rapidly giving way to severe wet weather, making the 30 June temperature highly sensitive to these incoming rain systems[2].

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 Polymarket Review UK, which mirrors the Polymarket order book at 0% fees.

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

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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Review UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.