Highest temperature in Paris on July 5?

Platform comparison

Market context

The real-world event hinges on whether Paris-Le Bourget will record a temperature in the highest bracket on 5 July 2026, despite the crowd-implied probability of 0% for a "YES" outcome. Historical data frames this as a classic underdog scenario: while Paris averages highs of 74–77°F (23–25°C) in July, rarely exceeding 88°F (31°C), the city has shattered its all-time record of 40.4°C (104.7°F) during recent heatwaves, with national peaks reaching 45.9°C (114.6°F) in southern France [1][4][7]. The consensus assumes typical summer moderation, yet the value spot lies in the contrarian angle that a severe heat dome, similar to those in 2003 and 2019, could push temperatures into the extreme range, making the 0% line a potential mispricing [2][3].

Traders must watch for announcements regarding the European heat dome's trajectory and dependencies on atmospheric pressure systems, as a recent heatwave already caused Paris to break its all-time high temperature record [7]. The catalyst is the potential for a sustained thermal marker, with the Met Office noting conditions expected to improve by Friday, suggesting a window for extreme readings if the dome persists [2]. Recent news confirms Paris is on alert for record-breaking temperatures as heat grips Spain and Germany, indicating that the 0% probability may ignore the volatility of early summer heatwaves that have previously driven temperatures above 42°C in Île-de-France [7][9]. The value sits in betting against the consensus that typical July weather will prevail, given the documented history of extreme spikes in the region.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on July 5? 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

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.

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.

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.