Highest temperature in Paris on August 11?

Platform comparison

Market context

Polymarket is pricing this Paris temperature contract at a **0% YES** crowd-implied probability, even though the on-chain market is live in **USDC on Polygon** and settles through **conditional tokens** once the Weather Underground reading for Paris-Le Bourget is final. The settlement source is the highest value in Weather Underground’s **Daily Observations** table, not the day-high summary, and revisions can matter until the first datapoint for the following date appears.[1]

That pricing sits against a hot late-summer backdrop rather than an ordinary August profile. Paris typically sees August highs in the mid-to-high 20s Celsius, but the city’s historical record for 11 August is far above that, with Météo-Paris listing a maximum of **39.5°C** on that date in 2003 and August records reaching **41.9°C** in 2019.[4][6] Recent forecast services also point to very warm conditions around the day, including highs in the low 30s Celsius and heat warnings, which helps explain why the market is clustered around a few upper-temperature bands rather than a broad spread.[7][13]

For traders, the key catalysts are the live Paris forecast evolution, any heat alerts, and the actual hourly observations at **Paris-Le Bourget Airport** as the day unfolds, because the market resolves from the station log rather than a city-wide summary. Weather Underground’s daily table can still be updated after the day ends, so a late adjustment to a peak observation can matter until the next day’s first datapoint is published.[1] The practical market angle is simple: if the station never prints a reading in the relevant band, the conditional tokens tied to that outcome expire worthless; if it does, those shares redeem at **$1** each on resolution.[1]

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 Polymarket Scam?, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

UK Frequently Asked Questions

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Polymarket Scam?. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.