Highest temperature in Hong Kong on August 4?

Platform comparison

Market context

Hong Kong’s heat has held in the low 30s in recent August outlooks, but showers and cloud cover remain the main brake on any spike beyond the seasonal norm. The latest forecast snapshots point to daytime highs around 29–31°C for 4 August, with humid conditions and intermittent rain making a modest cap on the day’s top reading more likely than a clear, uninterrupted warm-up.[1][2][8]

That framing fits the usual August pattern. Hong Kong’s climate data and seasonal guides describe August as the hottest and one of the wettest periods of the year, with typical daytime maxima near 31°C and frequent rain or thunderstorms; a one-day absolute maximum can still land below the monthly average if showers arrive early or persist through peak heating hours.[6][12][16] In that context, a crowd-implied 0% yes looks detached from the climatology unless the market is using a much higher threshold than the usual upper-20s to low-30s band.

Traders should watch the Hong Kong Observatory’s short-range forecast updates, rain warnings, and the timing of any convective showers through the afternoon, because those are the main drivers of the daily high. The resolution itself will depend on the Hong Kong Observatory’s final “Daily Extract” for 4 August, and the market cannot settle until that publication appears.[3][6][15] If temperatures stay close to the forecast range, the key question is whether the station’s one-decimal reading touches the relevant bucket before cloud and rain suppress the peak.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on August 4? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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.

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 Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.