Highest temperature in Paris on August 1?

Platform comparison

Market context

Polymarket is currently pricing this Paris temperature contract as a genuine range trade on the high 20s, not a binary heatwave bet: the market shows 28°C as the front-runner at 70%, with 29°C next at 19% and 0% for **YES** on the headline framing you provided. For a Polymarket user holding conditional tokens on Polygon and settling in USDC, the practical question is whether the Paris-Le Bourget Airport Station prints a daily high that lands in the listed band by the Wunderground cut-off, because the market resolves to the range containing the day’s highest recorded temperature.

The current read sits near early-August climatology for Paris, where monthly guides and historical-weather pages cluster around mid-20s Celsius highs, while Polymarket’s own event page notes recent model guidance around 27–29°C and cites climatological averages of 24–26°C. That makes the present pricing look anchored to a fairly ordinary summer pattern rather than an extreme outcome; in comparable Paris summer setups, the difference between 27°C, 28°C and 29°C often comes down to cloud cover, wind direction and the timing of afternoon sunshine rather than a wholesale regime shift.

The main catalysts are the short-range forecast runs and any late adjustment in the official station data stream that Wunderground uses for settlement. Traders should watch Météo-France updates, ensemble spread, and whether Atlantic airflow or cloud cover trims afternoon heating, because those factors move the final high by a degree or two and can flip the settlement band. Recent reporting on the French summer has also highlighted how quickly temperatures can surge in the north when a heat pattern strengthens, but for this market the key is whether Paris-Le Bourget actually breaks beyond the crowded 28–29°C zone before the first datapoint for the following day is published.

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 Kalshi UK, 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 Kalshi UK. 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.

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.