Highest temperature in Paris on July 23?

Platform comparison

Market context

Paris-Le Bourget Airport’s highest temperature on 23 July is the settlement variable, and the current market is pricing an outcome of **25°C** as a complete certainty, while the next band down sits at **0%** on the exchange screen. That leaves a large gap between the listed contract probability and the kind of uncertainty traders usually see in weather markets, especially when the reference point is a single airport station rather than city-wide averages.[1]

The historical frame is fairly ordinary for late July in Paris: one forecast source puts typical July highs around **26°C**, with other Paris climate summaries showing daytime warmth commonly in the mid-20s Celsius and a tendency towards hotter spells later in the month.[2][3] A separate Paris-and-Île-de-France forecast for 23 July points to **15°C to 28°C** in the region and no precipitation expected, which is consistent with a modestly warm day rather than an extreme outlier.[4] In cross-platform terms, the exchange-implied certainty around **25°C** looks much tighter than the broader weather range suggested by public forecasts and climate normals.[1][4]

For traders, the main catalysts are the final station-specific observations at Paris-Le Bourget and any late-day temperature spikes before the market’s 12:00 UTC settlement window closes. Because the contract resolves on the **highest** temperature recorded that day at the named station, an otherwise average day can still settle higher if the afternoon warms faster than expected. Short-term forecast updates, cloud cover changes, and timing of peak heating matter more than the morning reading, and there is no obvious official event schedule that would override the weather input itself.[4]

Sources: 1 · 2 · 3 · 4

Methodology

This page reviews Highest temperature in Paris on July 23? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi vs Polymarket, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 vs Polymarket. 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 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.

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.