Highest temperature in Paris on June 26?

Platform comparison

Active sub-markets

Market context

The real-world event hinges on whether Paris-Le Bourget will record a temperature exceeding 40°C on 26 June 2026, a threshold currently deemed impossible by the crowd with a 0% implied probability for the "YES" outcome. This stark consensus suggests traders believe extreme heat is confined to southern France or that the specific station will remain cool, yet historical data frames this as a potentially value-rich contrarian angle.

June in Paris typically sees daily highs rising from 69°F to 74°F, rarely exceeding 84°F, but the recent brutal heatwave across Europe has shattered previous norms, with France recording its hottest day ever at 44.3°C in Landes and a national record of 45.1°C just days prior [1][2][3]. While the all-time Paris record stands at 42.6°C in July, the unprecedented intensity of the current wave means the 0% probability may be ignoring the risk of a sudden spike, positioning the underdog as the favourite for value seekers who spot the disconnect between recent extremes and current pricing [7].

Traders must monitor the progression of the red heatwave alert across Île-de-France and any overnight temperature minima that fail to drop, as these are critical dependencies for a daytime maximum breach [4]. The settlement relies on Wunderground data for Paris-Le Bourget, so any official announcements regarding emergency cooling or wind shifts from the Atlantic could act as immediate catalysts, though the prevailing easterly flow currently sustains the heat [9]. With the national thermal indicator already breaking records, the consensus that Paris will stay below the threshold appears fragile, offering a clear value spot for those betting on the heatwave extending north.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on June 26? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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?

On Who Will Win, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 it cost to trade on Who Will Win?

Zero. Who Will Win routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Who Will Win triggers a quick verification flow that finishes in 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.