Lowest temperature in Hong Kong on August 8?

Platform comparison

Market context

Polymarket is pricing the lowest Hong Kong Observatory temperature on 8 August as a **0% YES** outcome, with settlement in USDC on Polygon through conditional tokens once the Hong Kong Observatory publishes the final Daily Extract. Because the market resolves to the HKO’s “Absolute Daily Min (deg. C)” for that date, the relevant object is not the daytime high but the coldest one-decimal Celsius reading logged at the Observatory before the extract is finalised.

That 0% price sits against a climate profile that is structurally unfriendly to cold prints. HKO’s 1991–2020 normals put 8 August’s mean minimum temperature at **26.9°C**, with an average mean temperature of **29.0°C** and mean maximum of **31.7°C**[1]. Generic August climate datasets for Hong Kong also show persistent warmth, with average lows around the mid-to-high 20s Celsius and only limited day-to-day deviation[2][5]. In practical market terms, a “YES” on a low-temperature band would usually require an unusual synoptic setup for Hong Kong, rather than a routine summer night.

Traders should watch the Observatory’s short-range readings and any weather warnings, but the key dependency is the publication of the final daily climate extract, since the market cannot resolve until that file is posted[6][10]. At 3 a.m. Hong Kong time on 8 August 2026, the Observatory reported **29°C** at the station, with nearby sites mostly in the **27–30°C** range[13]. That makes an outlier minimum materially colder than the current overnight pattern, and it explains why the contract can sit at a zero-implied price even before the official settlement data appears.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Lowest temperature in Hong Kong on August 8? 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

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.

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.