Highest temperature in Paris on July 22?

Platform comparison

Market context

Paris-Le Bourget Airport is the settlement location, so the key input is the day’s **highest observed temperature** there, not the city-wide average or the noon reading. At 16:00 UTC, BBC Weather showed Paris-Le Bourget at **21°C**, with light northerly wind, 41% humidity, and pressure at 1016 mb and falling, which is a useful live anchor for a programme that prices the *daily maximum* rather than the instantaneous temperature.[1]

A **0% YES** crowd price is usually what you see when the market is effectively treating the target band as unreachable, or when the contract design is narrow enough that traders have not yet recalibrated to the actual weather path. For a programmatic approach, the relevant logic is simple: compare live observations and short-range forecasts against the contract’s temperature brackets, then update as the afternoon warming cycle plays out; on a summer day in Paris, the highest reading often arrives later than the first post-lunch datapoint, so a bot watching only a single snapshot can miss the move.[1]

The main catalysts are the same ones that move any intraday temperature market: cloud cover, rain bands, wind shifts, and whether the local heating trend survives into the settlement window. Traders should watch the Paris-Le Bourget station feed closely on Wunderground, because the market resolves to the highest Celsius temperature recorded there on 22 July 2026, and small changes in the late afternoon can decide which range wins.[1]

Sources: 1

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.

FAQ

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 Kalshi Fees. 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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

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.