Highest temperature in Hong Kong on June 29?

Platform comparison

Market context

The real-world event is the daily maximum temperature recorded by the Hong Kong Observatory on 29 June 2026, measured in degrees Celsius to one decimal place. This single data point will determine which temperature range the prediction market resolves to, with the settlement window closing at 12:00 UTC on that date once the official "Daily Extract" is published.

Historical June data frames the current 0% crowd-implied probability for a "YES" outcome as a likely mispricing. Recent years show Hong Kong routinely hitting 33–35°C in late June, with 2026 forecasts indicating above-normal temperatures and daily highs ranging from 29–32°C (87–91°F) [1][2]. The Observatory has already warned of extreme heat hitting 37°C in the New Territories this week, and 2026 is projected to be abnormally hot following the hottest winter in recent memory [3][4]. A programmatically built trader would script a bot to pull the "Absolute Daily Max" from the HKO climate API at 12:01 UTC, comparing it against the market’s resolution ranges to execute conditional orders before the data finalises.

Key catalysts include the HKO’s seasonal forecast updates and real-time heat warnings, which directly influence temperature expectations. The Observatory’s May 2026 assessment confirms above-normal temperatures for June–August due to ENSO status and climate models [2]. Traders should monitor the HKO’s daily weather summaries for sudden spikes, as seen when Hong Kong recorded its hottest day of 2026 at 34.6°C with a hail warning [5]. A conditional order strategy would trigger buys if the 10:00 UTC preliminary reading exceeds 32°C, anticipating the final "Daily Extract" will confirm a high maximum. The market cannot resolve until the official data is published, making the 12:00 UTC deadline critical for settlement [9].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi Fees, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Kalshi Fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 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.

Do I need to KYC for this market?

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