Highest temperature in London on June 28?

Platform comparison

Market context

The underlying event is the highest temperature recorded at London City Airport on 28 June 2026, with current markets assigning zero probability to any outcome above the lowest range. This 0% YES implies the crowd expects temperatures to remain well below typical summer highs, a stark contrast to recent extremes where London hit 35.1°C on 24 June and the UK shattered its June record at 36.1°C just days prior[7][9].

Historical data shows London City Airport’s warm season runs from 16 June to 8 September, with average daily highs exceeding 67°F (19.4°C)[5]. Yet current forecasts for 28 June predict a maximum of 26°C, aligning with the crowd’s low expectations despite the recent heatwave[2][3]. The divergence between past records and current pricing suggests traders are betting on a rapid cooldown after the extreme heat, rather than sustained high temperatures.

Traders should monitor Met Office updates and any sudden shifts in weather models, as the market leans heavily on the absence of a declared heat emergency for this specific date[2]. With no scheduled political debates or campaign-finance disclosures tied to weather outcomes, the primary catalyst remains real-time temperature data from Wunderground, the official resolution source. The market’s 0% stance reflects confidence that 28 June will not replicate the record-breaking conditions of 24–27 June.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Political prediction markets differ structurally from sports betting: thinner liquidity, longer settlement windows, higher sensitivity to single news events. This page shows the live Polymarket quote for Highest temperature in London on June 28? plus platform attributes for the three reference venues, so you can see at a glance where the deepest market for this question sits.

Resolution & payout

For political markets the resolution source is decisive. Polymarket defines a concrete source per contract (e.g. AP, Reuters, official electoral commission) and uses the UMA Optimistic Oracle as the on-chain dispute mechanism. With a clearly defined outcome the USDC payout lands within minutes of the final confirmation.

FAQ

What resolution source is used for elections?

Polymarket defines the source per contract — usually Associated Press (AP Race Call), Reuters or the official electoral commission. The source is stated in contract details before the market opens.

Can prediction markets influence election outcomes?

Markets reflect expectations rather than create them. Studies show public-facing markets can anchor expectations, but don't influence the underlying outcome. Political markets are information, not advocacy.

Which platform has the deepest political liquidity?

Polymarket — by far. US 2024 presidential volume was ~$3.5B vs Kalshi (~$200M) and Betfair (~$120M). Where Polymarket is geo-blocked, brokers like Election Predictions UK route into the same order book at 0% fees.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Why do Polymarket and Kalshi differ on elections?

Kalshi must follow CFTC compliance — strict definitions, clear resolution sources, US citizens only with KYC. Polymarket operates globally without CFTC oversight — deeper liquidity, but also higher regulatory risk.