Highest temperature in London on June 6?

Platform comparison

Active sub-markets

Market context

On 6 June 2026, London City Airport's weather station will record a daily high temperature in Celsius. The market resolves to whichever temperature band captures that peak reading, with settlement occurring at midday UTC on the day itself. Wunderground's historical data for this specific station serves as the authoritative source, making station-selection precision critical—London City Airport sits in East London and experiences microclimatic variation from central London or Heathrow readings that traders sometimes conflate.

June temperatures at London City Airport historically range between 18–24°C for daily highs, with extremes rarely exceeding 27°C except during heat waves. The 0% crowd probability suggests either thin liquidity on this particular date-location pairing or genuine uncertainty about whether the market will attract sufficient trading volume to establish meaningful odds. Comparable weather markets on Kalshi and Betfair show stronger participation for major UK temperature thresholds (e.g., "Will UK exceed 30°C?"), whilst niche station-specific markets often languish with wide bid-ask spreads and minimal implied probabilities across all bands.

Traders should monitor the Met Office's extended forecast for early June 2026 as the settlement date approaches; any Atlantic high-pressure system or continental warm air advection would shift probability mass toward higher temperature bands. Fee structures differ materially across platforms here—Polymarket's 2% maker-taker model versus Kalshi's flat structure will affect position sizing for low-probability outcomes. Smarkets' decimal odds display may obscure the true probability distribution across temperature ranges compared to explicit percentage displays on rival venues.

Methodology

We read Highest temperature in London on June 6? 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.

Is this market available outside the US?

Polymarket Alternative UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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.

Do I need to KYC for this market?

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