Highest temperature in Hong Kong on May 25?

Platform comparison

Active sub-markets

Market context

On 25 May 2026, the Hong Kong Observatory will record a daily maximum temperature in Celsius, and Polymarket traders are currently pricing all outcome ranges at zero probability—a technical artefact of how conditional tokens settle on Polygon when no volume has accumulated. The market structure divides the day's high into discrete temperature bands, with USDC collateral backing whichever range ultimately contains the Observatory's official "Absolute Daily Max" reading from their Daily Extract dataset. Settlement depends entirely on the Observatory finalising its data, which typically occurs within days of observation but can extend if quality checks are required.

Hong Kong's May climate sits at the threshold between spring and early summer. Historical Observatory records show May 25 highs cluster between 28–32°C, with occasional outliers reaching 33°C during heat waves or pushing below 27°C in cooler years. The 0% crowd probability reflects the market's infancy rather than any meteorological impossibility; similar weather markets on Polymarket show meaningful volume only after seasonal patterns become clearer and traders build conviction around specific temperature bands.

Traders monitoring this contract should track the Hong Kong Meteorological Society's seasonal forecasts and any El Niño or La Niña updates from late 2025, as these drive May temperature variance. The Observatory publishes monthly climate summaries with historical comparisons, available on their public database. Any tropical cyclone activity in the weeks preceding 25 May could suppress temperatures, whilst high-pressure systems typically elevate them. The settlement window closes at 12:00 UTC on the resolution date, after which the Observatory's finalised reading becomes binding.

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, 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?

On PolyGram, which mirrors the Polymarket order book at 0% fees. 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.

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?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.