Highest temperature in London on June 16?

Platform comparison

Active sub-markets

Market context

On 16 June 2026, the highest temperature recorded at London City Airport will fall into one of several defined ranges. The settlement will draw from Wunderground's historical weather database for that specific station and date, with resolution occurring after the settlement window closes on 16 June at 12:00 UTC. USDC settlement follows standard on-chain mechanics once the temperature data is confirmed and the market resolves to the appropriate bracket.

London's June temperatures typically range between 18–24°C, with extremes occasionally reaching 27–28°C during warmer years. Historical data from the Met Office shows that temperatures above 25°C on mid-June dates occur in roughly one-third of years, whilst readings exceeding 30°C remain rare for this period and location. The current crowd-implied probability of 0% YES suggests traders are pricing in a specific temperature threshold as highly unlikely; understanding which range carries that assessment requires examining the exact bracket definitions against seasonal norms.

Traders should monitor UK weather forecasts released in the days preceding 16 June, particularly from the Met Office and BBC Weather, which typically provide reliable five-to-ten-day outlooks. Atlantic pressure systems and jet stream positioning in early June will influence whether warm continental air reaches southern England or cooler maritime conditions prevail. Any significant heatwave warnings issued by the UK Health Security Agency in the fortnight before settlement would shift probability distributions materially, as would anomalous warming patterns tracked by European weather models.

Methodology

This page reads Highest temperature in London on June 16? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed for comparison. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

Where can I trade this market with the lowest fees?

On BTC Prediction, 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?

BTC Prediction 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.

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.

What does it cost to trade on BTC Prediction?

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

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.