Highest temperature in Hong Kong on July 1?

Platform comparison

Market context

The real-world event at hand is the highest temperature recorded by the Hong Kong Observatory on 1 July 2026, measured in degrees Celsius to one decimal place. This market resolves to the temperature range containing that peak reading, with the official data sourced from the Observatory’s finalized “Daily Extract” once published. The current crowd-implied probability of 0% for a YES outcome suggests the market expects the temperature to fall outside the specified range, likely below 33°C, despite Hong Kong’s typical July heat.

Historical data frames this probability sharply: July is consistently Hong Kong’s hottest month, with an average high of 32.9°C (89°F) and record highs reaching 33°C or more in recent years. In 2007, the monthly mean maximum temperature hit 32.9°C, and the Hong Kong Observatory confirmed July 2023 as the city’s hottest month on record, featuring the most hot days and nights since 1884[2]. Forecast models for July 2026 predict daily highs between 29.4°C and 33.9°C (85°F to 93°F), with an average of 32.2°C (90°F)[3]. This historical context makes a 0% probability for 33°C+ appear unusually low, especially given the sharp overnight repricing seen in similar markets where the 33°C outcome traded at 54.5% after a 21.5% surge[1].

Traders should monitor the Hong Kong Observatory’s daily weather summaries and the release timeline for the “Daily Extract,” as resolution cannot occur until this data is finalized. Recent climate reports indicate rising summer temperatures, with July 2023 setting new benchmarks for hot nights and days[2]. A key catalyst is the Observatory’s monthly weather summary for July 2026, which will be published shortly after the month ends and could confirm whether peak temperatures exceeded 33°C. Programmatic approaches to this market would involve automated scripts querying the Observatory’s climatological data portal[7] for real-time updates on the “Absolute Daily Max” value, triggering conditional orders once the data is confirmed. The settlement window ends 12:00 UTC on 1 July 2026, so any delay in data publication could impact timing.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on July 1? 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

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

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Review UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.