Highest temperature in London on July 31?

Platform comparison

Market context

London City Airport’s peak temperature on 31 July will be set by the day’s warmest reading at the station before the settlement cut-off, so the market is really a read on whether the east London site catches a hot afternoon spike rather than on London as a whole. A zero-per-cent YES price looks consistent with a baseline expectation that late-July highs in the capital usually sit in the low-to-mid 20s Celsius, although the city has clear upside in hot spells and airport sites can run differently from inland locations.[1][8]

The key historical comparison is 31 July 2020, when Heathrow reached 37.8°C and Kew Gardens 37.3°C during an exceptional nationwide heat episode; Met Office material also records 37.8°C at Heathrow and places it among the UK’s hottest days on record.[2][5][10] London’s absolute highs are therefore extreme enough to reach the upper 30s, but those readings are rare and tied to broader heatwave conditions rather than a typical summer day.[3][13] On more ordinary July 31s, London readings have been much lower, with Timeanddate’s July 2025 archive showing temperatures around the mid-20s Celsius and a 77°F peak in the afternoon, which is more representative of a standard late-July profile.[1]

For traders, the main catalysts are the forecast trend into the morning of 31 July, the timing of any Met Office or BBC reporting on southeast England heat, and whether the airport station benefits from a clear-sky, light-wind setup that can lift the afternoon maximum.[4][17] The current 2026 summer backdrop has already produced notable heat elsewhere in Britain, including 35.1°C at Wisley and a string of 34°C-plus days, so any fresh northward shift in models would matter quickly for a London airport maximum.[17][18] Since the market settles on the highest station temperature recorded through the day, a short-lived late-afternoon surge is enough to move the range outcome materially.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Football-specific comparison page for Highest temperature in London on July 31?. Polymarket's live quote (Polygon order book) plus platform attributes for the three reference venues. Sports markets reward liquidity — Polymarket and Betfair are materially deeper than Kalshi (US-focused) or Manifold (play-money).

Resolution & payout

Sports markets typically settle on official final-whistle plus league confirmation. Polymarket uses UMA Optimistic Oracle with a source URL per contract — usually official league data feeds or ESPN/Soccerway. Two-hour dispute window, then smart-contract payout in USDC.

FAQ

Are prediction markets better than sports betting?

Prediction markets tend toward tighter odds than bookmakers because they use peer-to-peer exchange rather than bookmaker margin. On major matches, Polymarket quotes typically sit 2-5% closer to the true probability model than bet365 or DraftKings.

When do sports markets resolve?

Typically within hours of the official final whistle. Polymarket uses UMA Optimistic Oracle with source URLs pointing at official league data feeds — e.g. the Premier League for EPL markets, UEFA for Champions League, FIFA for World Cup.

Can I bet on individual matches?

Yes, Polymarket lists every major Premier League / Champions League / World Cup match as its own market. Liquidity varies — top matches like El Clásico or a semi-final often have six-figure pools, lower-league games closer to three-figure.

Which sports markets are available?

Football (soccer) dominates — Champions League, World Cup, Premier League, La Liga, Bundesliga — followed by NFL, NBA, tennis Grand Slams, Formula 1, boxing/MMA. Resolution via official league source confirmation.

What's the difference between match odds and outright odds?

Match odds cover a single game ("Bayern beats BVB"). Outright odds are long-term aggregates ("Bayern wins the league"). Outright markets have deeper liquidity; match markets have faster resolution.