Highest temperature in Hong Kong on July 4?

Platform comparison

Market context

The real-world event hinges on the highest temperature recorded by the Hong Kong Observatory on 4 July 2026, measured in degrees Celsius to one decimal place. This market resolves to the specific temperature range containing that peak reading once the data is finalized in the official "Daily Extract". With the current crowd-implied probability at 0% for a "YES" outcome, the market suggests the crowd believes the temperature will fall outside the defined range, though the specific range in question remains unstated in the prompt.

Historically, July is Hong Kong’s hottest month, with average highs around 89°F (31.7°C) and recorded peaks reaching 35.7°C in recent years[3]. The Hong Kong Observatory confirmed July 2023 as the city’s hottest month on record, featuring the highest number of hot days and nights since 1884[9]. Current forecasts for July 2026 indicate daily highs ranging from 86°F to 96°F (30°C to 35.6°C), with overnight lows between 79°F and 82°F[1]. A power-user approaching this programmatically would script a bot to poll the Observatory’s climatological API daily, parsing the "Absolute Daily Max" field to trigger conditional orders before the 2026-07-04 settlement window closes.

Traders must monitor the Observatory’s release schedule for the "Daily Extract", as the market cannot resolve until this data is published[6]. Recent anomalies, such as the 92.1°F (33.4°C) peak recorded on 2 July 2026, suggest volatile short-term spikes that could impact the 4 July reading[5]. The primary catalyst is the official confirmation of the daily maximum, which depends on the Observatory’s internal validation process. Any delay in the "Daily Extract" publication could extend the settlement timeline, requiring traders to adjust their conditional order logic accordingly.

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Methodology

This page reviews Highest temperature in Hong Kong on July 4? 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 Polymarket Review UK, which mirrors the Polymarket order book at 0% fees.

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

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 Polymarket Review UK. 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'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.