Highest temperature in Hong Kong on August 10?

Platform comparison

Market context

Hong Kong’s hottest reading is determined by the Hong Kong Observatory’s official maximum for the day, reported to one decimal place, so the trade is really about whether the final “Absolute Daily Max” lands above or below the relevant band once the daily extract is published. The current 0% implied probability means the market is pricing no chance of a settlement in the YES range, even though today’s conditions are already unusually warm by local standards, with forecasts around the mid-30s °C and nearby stations at times running hotter than the Observatory’s headquarters reading.[9][10][11]

That framing matters because August in Hong Kong is already a high-heat month: the long-run daily normal maximum on 10 August is 31.4°C, while recent August cases have shown the Observatory can still post low-to-mid-30s maxima even without a record event.[5][3] The larger reference point is the recent record heat: the Observatory reported 36.9°C on 9 August 2026, the city’s highest temperature since records began in 1884, which tells you the upper tail is not theoretical and that adjacent stations can exceed the headquarters reading by several degrees.[2][7][16]

A power-user would monitor the Observatory’s hourly statements, the day’s synoptic setup, and the eventual publication of the Daily Extract, then automate a check against the settlement bands once the final figure is posted. The key dependency is not just the live temperature feed but the official retrospective extract, because the market cannot resolve until that record appears; recent coverage also tied the extreme heat to Typhoon Dolphin’s warm-air subsidence, a reminder that tropical-cyclone edges can materially shift Hong Kong maxima within hours.[2][15][19]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on August 10? 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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Kalshi Fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 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 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.