Highest temperature in Hong Kong on July 17?

Platform comparison

Market context

Hong Kong faces its peak summer heat today as the Hong Kong Observatory records the absolute daily maximum temperature for 17 July 2026. The prediction market for this event currently shows a 0% implied probability for any outcome resolving as "YES" under a binary framing, yet the underlying contract actually resolves to specific Celsius ranges. Polymarket data identifies 29°C as the frontrunner with a 37% chance, while 30°C holds the next closest position at 29% [1]. This divergence highlights a critical discrepancy between the binary crowd-implied probability of 0% and the granular range-based odds where traders are actively pricing in mid-summer warmth.

Historical July data for Hong Kong typically sees maximum temperatures hovering between 28°C and 32°C, making the 29°C and 30°C ranges the most statistically probable outcomes. The current market pricing aligns with these comparable cases, as the collective view heavily favours temperatures in the high twenties rather than extreme peaks above 33°C or cooler days below 27°C. Traders comparing platforms should note that while some sportsbooks might offer binary weather lines with different liquidity, the prediction market’s range-specific odds provide a more precise reflection of the meteorological consensus for this specific date.

Key catalysts for this contract include the finalisation of the "Daily Extract" data from the Hong Kong Observatory, which will publish the "Absolute Daily Max (deg. C)" once the settlement window closes at 12:00:00Z on 17 July 2026. No external announcements or schedules will alter the outcome, as the resolution relies solely on this official meteorological record. Analysts monitoring the contract should watch for real-time updates on the Polymarket interface, where odds shift as traders buy or sell shares based on live weather conditions and the evolving collective view of the day’s peak heat [1].

Sources: 1

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

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.

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.

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.