Highest temperature in Paris on July 15?

Platform comparison

Market context

Paris is experiencing its third heatwave of 2026, with Météo-France downgrading the regional alert from red to orange just as a storm system begins to push the hot air mass westward [5]. Despite this cooling trend, Wednesday’s forecast still predicts highs of 32–34°C across the Île-de-France, meaning the 0% crowd-implied probability for a record-breaking temperature is likely premature given the persistent heat dome [5][12]. The market’s zero probability ignores the reality that July 2026 has already been significantly warmer than historical averages, with daily highs in early July reaching 35–36°C and the month’s trend favouring sustained warmth rather than a return to the 25°C average [3][12].

Historical precedents show that Paris frequently exceeds 35°C during July heatwaves, with the nation recording its hottest day ever on 23 June 2026 at nearly 40°C [8][9]. The current 0% probability suggests traders believe the storm system will fully extinguish the heatwave before 15 July, yet Météo-France warns the retreat is incomplete and temperatures will remain oppressive through Wednesday afternoon [5]. Traders should monitor the hourly evolution of the storm system’s advance and any updated Météo-France warnings, as the resolution depends on the peak temperature at Paris-Le Bourget Airport before 12:00 UTC on 15 July [5]. A delay in the storm’s arrival or a secondary heat pulse could easily push the day’s maximum into the 35°C+ range, invalidating the current market stance.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on July 15? 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

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

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.

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 Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.