Highest temperature in Paris on July 26?

Platform comparison

Market context

Paris is in the middle of a late-July heat episode, and the market is about the highest temperature reached at Paris-Le Bourget Airport during the day, not the citywide average. That matters because airport observations can run a little differently from central Paris, but the contract settles on the Wunderground daily high for the station, so the key variable is whether the day’s peak landed in the mid-to-high 30s or pushed to 40°C. Recent coverage has warned of Paris temperatures expected around 36–39°C, with some forecasts allowing for 40°C on the hottest afternoons[2].

The current crowd-implied probability of 0% YES looks hard to reconcile with the weather backdrop unless traders are treating the contract as already effectively out of the money or are waiting for the settlement observation to be finalised. In comparable Paris July heat spells, daytime highs above 35°C are not unusual during a strong heat dome, and media guidance has repeatedly singled out the early afternoon as the most likely window for the daily maximum[1][2]. That is the main historical frame: when synoptic conditions lock in hot, dry air over northern France, the odds shift rapidly towards an extreme daily high rather than a mild summer reading.

The trading catalyst is the late-day evolution of the heat dome and any cooling influence from Atlantic air or thunderstorms, both of which could cap the maximum or bring it down after the peak has already been set[2]. Because the settlement window ends at 12:00 UTC and the source is the recorded daily high at Paris-Le Bourget, traders should watch the station’s reported maximum rather than headline city forecasts, plus any last-minute adjustments in regional weather coverage. Wego’s Paris heatwave guidance also points to the hottest period falling roughly between 12pm and 4pm local time, which is the key interval for the day’s top reading[1].

Sources: 1 · 2 · 3

Methodology

We track Highest temperature in Paris on July 26? 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

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 Best Prediction Markets UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.