Highest temperature in Hong Kong on August 17?

Platform comparison

Market context

On 17 August 2026, the Hong Kong Observatory will record the day's maximum temperature in Celsius to one decimal place, and this market resolves to whichever temperature band captures that figure. Polymarket currently prices all outcomes at 0% YES, reflecting the standard state of markets for future weather events before meaningful historical data or seasonal forecasts crystallise the probability distribution across temperature ranges.

Hong Kong's August climate is characterised by intense heat and humidity during the tail end of the southwest monsoon season. Historical records from the Observatory show August daily maxima typically range between 31–33°C, with extreme heat occasionally pushing toward 35°C during particularly intense heat waves. The city's all-time August high stands at 36.3°C, recorded in 1967, though such extremes remain rare. Recent Augusts have seen occasional days exceeding 34°C, particularly in 2015 and 2023 when heat domes settled over the region. These precedents establish the baseline against which traders should calibrate their position: the most probable outcomes cluster in the 31–34°C bands, with progressively lower odds attached to either cooler or more extreme readings.

Traders monitoring this contract should track the Asian summer monsoon forecast and any El Niño or La Niña signals from meteorological agencies, as these drive regional temperature anomalies months in advance. The Hong Kong Observatory publishes seasonal outlooks typically in June and July; their August 2026 forecast, once released, will offer the first official guidance on whether conditions favour above or below-normal heat. Real-time catalysts closer to mid-August include tropical cyclone activity in the Western Pacific, which can suppress temperatures through cloud cover and rainfall, and any sustained high-pressure systems that would amplify daytime heating.

Methodology

This page reviews Highest temperature in Hong Kong on August 17? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

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