Highest temperature in London on August 4?

Platform comparison

Market context

London City Airport’s maximum temperature on 4 August will be set by the day’s actual reading, not by the broad August average, and the published London outlooks mostly point to a modestly warm but not exceptional day. London’s August norm is around 21–22°C for daytime highs, with averages for the month clustering near 22°C and overnight lows in the mid-teens[2][4][7][16]. That matters because a market priced at 0% YES is implicitly treating a very hot outcome as remote, and the historical framing supports that: late-summer London commonly sits in the low 20s rather than the high 20s or 30s[1][7][16].

The main catalyst is the near-term forecast track rather than any scheduled political-style event, because the settlement source is an airport station reading due by midday UTC. Recent local forecasts cited in the search results have ranged from about 21°C to 27°C for 4 August, with some outlets describing drizzle, light rain showers or overcast conditions and others leaving room for a warmer spell[3][5][8][13]. For traders, the key dependency is whether cloud and showers cap the airport’s midday warmth or whether a brief sunny window allows the daily maximum to print above the mid-20s; any updated forecast from a mainstream weather service will matter more than the month-long average[2][3][5][8].

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 August 4? 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.

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.

Are political prediction markets legal in my country?

It varies. They sit in legal gray areas in most jurisdictions. Polymarket is geo-blocked from US/UK/EU; some broker frontends have a different geo footprint. Trade only with capital you can afford to lose, and only if you understand the legal status in your jurisdiction.

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.