Highest temperature in London on June 2?

Market context

On 2 June 2026, the highest temperature recorded at London City Airport will fall within one of several defined ranges. The settlement mechanism relies on historical weather data from Weather Underground, specifically the daily maximum temperature for that location. Traders need to verify the temperature unit setting (Celsius vs Fahrenheit) when accessing the resolution source, as the interface defaults may differ from the market's stated denomination.

London's June temperatures typically range between 18–24°C, with historical maxima occasionally exceeding 28°C during warm spells. The current 0% crowd probability suggests either extreme confidence in a specific temperature band or insufficient liquidity across the full range. Comparable June weather patterns from 2015–2024 show that temperatures above 25°C occur roughly 30–40% of the time, providing a baseline for calibrating position sizing against the implied distribution.

Traders monitoring this market should track UK Met Office forecasts released in the week preceding 2 June, as these typically carry the highest predictive value for daily maxima. Atmospheric pressure systems and jet stream positioning in late May determine whether continental warm air reaches the UK or Atlantic systems dominate. For programmatic approaches, integrating automated pulls from Weather Underground's historical API after settlement would eliminate manual verification delays, though the 12:00 UTC window requires accounting for potential data refresh lags in the underlying source.

Methodology

This page reviews Highest temperature in London on June 2? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Resolution source: This market settles from the official publication at https://www.wunderground.com/history/daily/gb/london/EGLC. A proposer submits the result to the UMA Optimistic Oracle on Polygon, the two-hour challenge window opens, and the smart contract pays out in USDC.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.