Highest temperature in London on June 19?

Platform comparison

Active sub-markets

Market context

London City Airport is finishing the day with a warm June high in the high 20s Celsius, and the live readings already make the current 0% crowd price look more like a pricing glitch than a strong view on the outcome. The key settlement point is the highest temperature recorded at the airport station before noon UTC, so the relevant question is whether the midday-to-early-afternoon peak reached the upper 20s or pushed into 30°C territory before the window closed.[1][8]

Recent comparables point to a market that usually trades on the day’s observed maximum rather than the month’s seasonal norm. BBC Weather had forecast 25°C for London City Airport with no precipitation expected, while The Weather Network showed a 30°C high for the airport on the same date, and current METAR-style reporting placed the airport near 27–29°C in the afternoon. That spread is enough to keep range pricing live, but it does not support a zero-probability book unless the market is dominated by funding friction rather than weather expectations.[2][1][8]

For traders, the more important catalyst is not a fresh forecast headline but the mechanics of getting money in and out quickly. Deposit methods that settle fast, such as **Klarna** or **SEPA**, can widen participation when a market is still open, while withdrawal rails such as **USDC** reduce the delay between winning a position and recycling capital into the next one. In practice, the depth here is likely to be driven by how smoothly cash can reach the book before noon UTC and how quickly it can leave afterwards, rather than by late-breaking weather alone.[1][6]

Sources: 1 · 2 · 3 · 4 · 5

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 Polymarket Klarna UK, 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 Polymarket Klarna 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 Klarna 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'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 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.