Highest temperature in Hong Kong on August 7?

Platform comparison

Market context

Hong Kong’s highest temperature on 7 August will be set by the Hong Kong Observatory’s final “Absolute Daily Max” reading for the day, and the market will only settle once that daily extract is published. Early official readings point to a hot day: at 4 a.m. the Observatory reported 28°C, with the public forecast calling for around 34°C in urban areas and a couple of degrees higher in the New Territories, plus an outlook for extreme heat to persist over the next few days.[1][6]

The current **0% YES** looks disconnected from the weather setup rather than from any known settlement issue. Hong Kong’s August climate usually sits in a high-heat, high-humidity regime, so a daily maximum in the low-to-mid 30s is normal, while 36°C-plus outcomes are less common but still explicitly flagged by the Observatory for parts of the New Territories this weekend.[6][11] That makes sportsbook-style temperature lines centred around the mid-30s, and public forecast products showing highs of 34–37°C, broadly consistent with a market that should not be priced near zero on a straightforward hot-day contract.[2][5][8]

For traders, the main catalysts are the Observatory’s daytime hourly updates, any changes to the local forecast, and whether showers or squally thunderstorms arrive later than expected, since cloud and rain can cap the maximum temperature.[6][14] The key dependency is the final HKO daily extract for 7 August, not live station reads, so intraday spikes matter only if they are captured in the day’s official maximum.[1] The market will not resolve until that publication is finalised, which means settlement timing depends on the Observatory’s reporting schedule rather than the 12:00 UTC cut-off alone.[1]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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 Best Prediction Markets 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.