Highest temperature in Paris on July 2?

Platform comparison

Market context

On 2 July 2026, Paris faces a critical weather test as the city enters its second potential heatwave of the year, with meteorologists forecasting highs near 37°C. The market currently assigns a 0% implied probability to temperatures exceeding the upper threshold, reflecting a consensus that the day will remain within the moderate range. However, historical data suggests this view may be overly cautious: long-term averages for Paris in July show daytime peaks of 24°C, yet recent events have shattered expectations, with Paris hitting 40.3°C just days ago during France’s record-breaking heatwave [2].

The catalyst for traders to watch is Météo-France’s projection that extreme heat could return from 6 July and persist until 14 July, with a strong probability of a second heatwave [2]. While climatologists caution that precise predictions beyond 10 days are impossible, the agency explicitly confirmed the likelihood of renewed extreme conditions [2]. This creates a contrarian angle: the market’s dismissal of high temperatures ignores the agency’s own warning of a second wave, suggesting value may sit on the underdog side if the heatwave arrives earlier than forecast. Recent reports indicate Paris is about to experience its second heatwave starting Wednesday, with highs projected at 37°C, nearly matching the all-time record [7].

The consensus remains anchored to the recent cooling trend, yet the underlying real-world event points to volatile conditions where a single shift in atmospheric pressure could push temperatures beyond the threshold. Traders should monitor daily updates from Wunderground, the official resolution source, for any deviation from the 37°C forecast [2]. The value spot lies in the discrepancy between the market’s 0% probability and the meteorological agency’s explicit confirmation of a second heatwave, making the underdog a compelling, albeit risky, position.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on July 2? 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 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 Who Will Win 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.