Highest temperature in Hong Kong on May 26?

Platform comparison

Active sub-markets

Market context

On 26 May 2026, the Hong Kong Observatory will record the day's peak temperature in Celsius, and this market will settle to whichever range bracket contains that official reading. The settlement hinges on the Observatory's finalised "Absolute Daily Max" figure published in their Daily Extract dataset—a process that typically completes within days of the observation date, though delays can occur during periods of data verification.

Hong Kong's May temperatures historically cluster in the 28–32°C range, with occasional spikes above 33°C during early heat waves or when southwesterly flows intensify ahead of the monsoon transition. The 0% crowd probability reflected here suggests either thin liquidity on this specific date-bracket combination or a mismatch between available ranges and trader expectations. Comparing across platforms: Polymarket's decimal odds format and tiered fee structure (0.2% maker, 2% taker) differ markedly from Kalshi's fixed 2% fee on both sides and Betfair's commission-on-profit model, which can shift the effective cost of holding positions through May. Smarkets charges 5% on net winnings, making longer-dated weather markets more expensive to hold there. KYC requirements also diverge—Polymarket and Kalshi enforce full verification, whilst Betfair and Smarkets operate with lighter onboarding in certain jurisdictions—affecting which traders can access this market at all.

Watch for the Hong Kong Meteorological Society's seasonal outlooks and any tropical cyclone activity in the Western Pacific during late May, as these can shift temperature trajectories sharply. The Observatory publishes monthly climate summaries that occasionally revise earlier daily maxima, though such revisions are rare after initial publication.

Methodology

We read Highest temperature in Hong Kong on May 26? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live quote comes directly from the Polygon order book; the other three are listed with their platform attributes — fees, KYC, settlement currency, payment options — because a 1:1 contract comparison without API access would be guesswork.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Alternative UK, 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 does it cost to trade on Polymarket Alternative UK?

Zero. Polymarket Alternative UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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.