Highest temperature in Hong Kong on June 22?

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Active sub-markets

Market context

Hong Kong’s observatory maximum for 22 June will settle on the day’s highest **Absolute Daily Max** in Celsius, so traders are really forecasting the intraday heat print rather than the evening close. In programmatic terms, the clean way to handle it is to map the HKO daily extract once published, parse the one-decimal value, then bucket that figure into the market’s listed ranges; until then, the event remains unresolved because the official data is the only settlement source.[1]

The current 0% crowd-implied probability is best read as an early positioning artefact rather than a firm view on the weather. Hong Kong’s June climatology is already warm, and HKO’s own June statistics show the month regularly produces high maxima in the low- to mid-30s Celsius, with hot spells not unusual.[2][3] Recent HKO reporting also shows that June has already delivered very hot days in prior years, including 35.6°C in June 2025, which is a useful benchmark for how quickly the upper bins can become live when a ridge builds over southern China.[7]

For traders running bots, copy-trading, or conditional orders, the key catalysts are the HKO morning forecast updates, any special weather warnings, and the timing of the daily extract publication itself. The market can only close on the official figure, so the highest-liquidity move often comes when a forecast nudges expected maxima across a bin boundary, or when the observatory posts the final daily data after the observation window ends.[1][10] A practical workflow is to watch HKO’s forecast temperature range through the day, then compare it with the prior few June highs to judge whether the market should cluster around 31–33°C or push into the hotter tail.[2][3]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on June 22? 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

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

Where can I trade this market with the lowest fees?

On Polymarket App 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.

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 Polymarket App UK?

Zero. Polymarket App 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, Polymarket App UK triggers a quick verification flow that finishes in minutes.

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.