Highest temperature in London on July 16?

Platform comparison

Market context

London City Airport is forecast to hit 20°C today, yet the Polymarket contract for the highest temperature on 16 July 2026 prices the “YES” outcome at 0%, implying the market believes the event will not resolve within the selected range. On-chain, this conditional token sits on Polygon, settled in USDC, with the current frontrunner being 28°C at 54% probability and 29°C at 30% [1]. The zero per cent pricing reflects a mismatch between the live reading and the settlement window, which closes at 12:00 UTC tomorrow, not today’s afternoon conditions [2][3].

Historically, mid-July highs at EGLC have ranged from 18°C to 32°C, with 28°C appearing in 2022 and 2023 during heatwaves. The current 0% probability is anomalous compared to past years where similar dates saw temperatures well above 25°C, suggesting the market may be mispricing the likelihood of a late heat spike before the 12:00 UTC cutoff. Traders should note that Wunderground, the resolution source, records the peak for the full day, not just the current hour [1].

Watch the Met Office’s 18:00 UTC forecast update and any sudden southerly wind shifts, which could push temperatures higher before settlement. A recent BBC Weather alert noted falling pressure and southerly flow, conditions that often precede temperature rises in London [2]. No official announcements are pending, but the dependency on Wunderground’s daily max means traders must monitor real-time data until the settlement window closes.

Sources: 1 · 2 · 3

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Scam?, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Polymarket Scam?. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 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.