Highest temperature in Hong Kong on June 4?

Platform comparison

Active sub-markets

Market context

On 4 June 2026, the Hong Kong Observatory will record the day's maximum temperature in degrees Celsius. This market settles on that single data point, with resolution contingent on official publication in the Observatory's Daily Extract once the date passes and figures are finalised. The 0% crowd probability suggests either minimal trading activity or genuine uncertainty about which temperature band will occur.

Hong Kong's June climate sits at the threshold of the southwest monsoon season. Historical daily maxima for early June cluster between 28°C and 32°C, with occasional excursions above 33°C during heat waves or when tropical systems approach. The 2015 heatwave saw 35.3°C recorded on 23 June; more recently, June 2023 averaged around 30–31°C for daily highs. These precedents matter because they anchor reasonable expectation ranges. Polymarket's decimal odds format and Kalshi's binary structure will handle this differently—Kalshi typically offers yes/no on specific thresholds, whilst Polymarket's range-based settlement allows finer granularity. Betfair and Smarkets, with their commission-based fee models, may attract different trader profiles than Polymarket's maker-taker structure, particularly for niche weather markets with sparse liquidity.

Traders should monitor the Hong Kong Observatory's seasonal forecasts and any tropical cyclone advisories issued in late May or early June 2026, as these directly influence temperature outcomes. The settlement window closes at 12:00 UTC on 4 June, but actual Observatory data publication typically occurs within 24–48 hours thereafter, creating a lag between market close and final resolution. This timing dependency is material for cross-platform arbitrage or hedging strategies.

Methodology

This page compares Highest temperature in Hong Kong on June 4? 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 Polymarket Alternative UK, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket 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.

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?

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