Highest temperature in Paris on August 11?

Platform comparison

Market context

Paris’s highest temperature on 11 August will be measured at Le Bourget Airport and settled from Weather Underground’s **Daily Observations** table, so intraday swings matter more than the rounded high shown elsewhere. The market is pricing in a notably cautious outcome: the crowd-implied probability is still **0% YES**, even though the exchange listing points to **32°C** as the leading band and nearby forecasts sit mostly in the low-to-mid 30s Celsius. That gap suggests traders are either discounting the exact station reading, or expecting the realised maximum to land outside the most obvious headline ranges.[5][7][8][9][14]

The historical frame is straightforward: Paris can reach the high 30s in August, but that is still an extreme rather than the norm. Long-run August records for Paris show a 11 August maximum of **39.5°C** in 2003, while broader Paris history includes a **41.9°C** all-time high in 2019 and multiple August days above 37°C in warm years.[3][6][13] Against that backdrop, current forecasts from AccuWeather, The Weather Network and Thomas Cook cluster around **32°C to 34°C** for 11 August, with hotter temperatures building later in the week; that implies the market’s main question is not whether Paris is warm, but whether Le Bourget reaches the higher end of the day’s forecast band.[1][7][8]

For traders, the main catalysts are the morning-to-afternoon forecast updates, any heat warnings, and the first published hourly observation at the station that establishes the day’s true peak before settlement. AccuWeather already flags an **extreme high temperature warning** for Paris, while hour-by-hour forecasts from Timeanddate show temperatures rising into the late morning and early afternoon, which is when a revised peak could still be recorded.[9][14][15] The key cross-platform comparison is that sportsbook-style weather lines, forecast sites and the prediction market are all converging on heat, but only the contract depends on the exact station maximum and the final Daily Observations entry, not the generic city high.[5]

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 PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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.

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.

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.