Highest temperature in Paris on July 17?

Platform comparison

Market context

Paris will record its highest temperature for 17 July 2026 at the Paris-Le Bourget Airport Station, with the market settling on the specific Celsius range containing that peak. Today, Polymarket prices the contract such that the 26°C outcome dominates with an 84% implied probability, while 27°C sits at 18% and all other ranges, including any extreme heat, are priced at 0% [1]. This heavy weighting on 26°C reflects the crowd’s confidence in a mild mid-summer day rather than a heatwave, a stance that aligns with on-chain mechanics where USDC liquidity on Polygon flows into conditional tokens representing these discrete temperature bands.

Historically, mid-July highs in Paris often cluster between 24°C and 28°C, making the current 84% probability for 26°C a statistically grounded position rather than an outlier. Comparable cases from recent summers show that temperatures exceeding 30°C in mid-July are rare events, typically occurring only during prolonged continental heat domes, which supports the market’s near-zero pricing for extreme outcomes. The 0% crowd-implied probability for any outcome above 27°C suggests traders view a significant heat spike as implausible given current seasonal norms.

Traders should monitor daily forecasts from Météo-France and real-time updates on Wunderground, the official resolution source, for any sudden shifts in cloud cover or wind patterns that could nudge the peak temperature. While no specific announcements are pending, the settlement window ending 2026-07-17T12:00:00Z means the final reading will be locked in by midday UTC, leaving little room for late-day volatility to alter the outcome [1]. The dependency on a single station’s data means localised anomalies at Le Bourget could override broader regional trends, a nuance that conditional token holders must weigh against the dominant 26°C narrative.

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 PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.