Highest temperature in London on June 22?

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Market context

London’s heat has already pushed into the high 20s, and the latest spot forecasts for London City Airport still point to a warm afternoon rather than a sharp cool-down. BBC Weather currently shows 28°C for the airport today, while the Met Office forecast pegs Monday’s maximum at 27°C, with both services implying the day’s top could land in the 27–28°C band.[5][3]

That lines up with the market’s current centre of gravity: 27°C is priced as the clear frontrunner at 81%, with 28°C next at 19%.[1] In practical terms, that is a narrow distribution anchored around a warm but not exceptional London summer reading. The set-up matters because this market settles on the highest temperature recorded at London City Airport Station through the late-day window, so a few tenths of a degree in realised warmth can shift the final bucket.

The main catalysts now are the afternoon observation updates, any cloud-cover or breeze changes over east London, and whether the airport can squeeze out one more hourly peak before the settlement cut-off. BBC’s station reading already shows 13°C early in the day with southerly wind and falling pressure, which supports a live-but-still-controllable forecast path rather than a locked-in outcome.[5] If the warmth persists, 28°C remains the main upside risk; if the sea breeze or cloud arrives earlier, 27°C remains the more likely landing zone.[3][5]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

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

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FAQ

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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.