Highest temperature in Paris on July 7?

Platform comparison

Market context

A new heat dome is settling over Île-de-France, pushing Paris temperatures well above seasonal norms and making Tuesday, 7 July, the hottest day of the early week. Météo-France forecasts highs climbing to 36°C in Paris under mostly sunny skies, with warm nights offering little relief [1]. While the current crowd-implied probability for the highest temperature being in the 33°C range sits at 0% YES, short-range ensemble models from major weather services indicate a high probability of a maximum between 34–36°C, with 33°C currently the frontrunner at 56% in the market [2].

Historical context frames this probability carefully: the end-June heatwave saw Paris hit a record 40.9°C, the country’s hottest day since 1947, yet Météo-France states odds of reaching such extremes this week are low [1][6]. Traders should watch the evolution of the heat dome, which remains uncertain, and monitor daily updates from Météo-France for shifts in the forecast [1]. A small chance of storms later in the week could bring relief, but until then, dry conditions and high UV indices persist, with officials advising residents to avoid heavy exercise between noon and 6 pm [3]. The resolution will depend on the peak temperature recorded at Paris-Le Bourget Airport, sourced from Wunderground.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on July 7? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Today 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.