Highest temperature in Hong Kong on August 1?

Platform comparison

Market context

Hong Kong’s answer will come from the Hong Kong Observatory’s *Absolute Daily Max* for 1 August 2026, published in the Daily Extract after the day has been finalised, so the market is really a bet on whether that official peak lands inside the nominated temperature band. The Observatory’s long-run August normal for 1 August is a mean maximum of 31.6°C, which is a useful baseline for reading the current crowd price, but the settlement value is the day’s actual maximum, measured to one decimal place.[16][2]

Historically, early-August Hong Kong temperatures have often sat in the low-30s rather than the upper-20s, and recent Augusts have produced several high readings: 35.4°C on 5 August 2024 and 34.4°C on 10 August 2025 were both monthly maxima in their respective years.[10][14] That context makes a 0% implied probability on a “YES” outcome look like a thin-price view rather than a strong statement about weather fundamentals, especially because one hot afternoon can move the official daily high decisively in this market.[10][14]

For traders comparing platforms, the practical differences matter more here than the theme. Polymarket and Kalshi typically show implied probability directly, while Betfair and Smarkets price the same event through decimal odds, so a small move can look sharper or flatter depending on the format; fees also differ, with exchange-style commission more visible on Betfair and Smarkets, while access and KYC reach can be broader or narrower depending on jurisdiction and platform rules. The main catalyst is the Observatory’s intraday weather pattern on 1 August, especially whether a hot, stable air mass allows temperatures to peak before cloud, rain, or a sea-breeze shift caps the maximum; the official result cannot settle until the Daily Extract is posted.[4][16]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Hong Kong on August 1? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Robinhood Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Robinhood Prediction Markets has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.