Highest temperature in London on July 7?

Platform comparison

Market context

London on Tuesday, 7 July 2026, is forecast to reach a maximum of 31°C, slightly cooler than Monday’s 34°C peak, yet still well within heatwave territory with daytime highs not dipping below 32°C for the rest of the week [2]. The Met Office confirms this “dry and light” day will feature hazy sunshine and a light breeze, while forecasting models suggest the heatwave could persist until mid-July, with temperatures exceeding 30°C for up to ten consecutive days [2].

Historically, London’s July maxima have ranged from the upper 20s to low 30s Celsius, with 31°C emerging as the current leading outcome on Polymarket at 56% probability, followed by 32°C at 24% [1]. This aligns with recent patterns where heatwaves in early July have consistently pushed temperatures above 30°C, making the current 0% crowd-implied probability for the “YES” outcome (exactly 31°C) appear mispriced against the weight of comparable cases [1][2].

Traders should monitor the UKHSA’s yellow heat health alerts, active from 4 July until 11 July, which signal sustained high-risk conditions [2]. Additionally, watch for the Met Office’s updated forecasts for Wednesday and Thursday, when temperatures may peak at 34°C, potentially shifting market expectations toward higher ranges [2]. The resolution source, Wunderground, will record the daily maximum at London City Airport Station, so any sudden thunderstorm risk between 7–9 July—mentioned in regional outlooks—could introduce volatility [3][4]. On-chain, this contract trades in USDC on Polygon using conditional tokens, where prices reflect real-time sentiment on these meteorological dependencies.

Sources: 1 · 2 · 3 · 4 · 5

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 PolyGram, 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

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.

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 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.