Highest temperature in Paris on June 28?

Platform comparison

Market context

The underlying event is a forecast for extreme heat at Paris-Le Bourget on 28 June 2026, yet the crowd-implied probability sits at 0% for the highest temperature hitting a specific high range. This near-zero valuation suggests the market believes such temperatures are virtually impossible for Paris on that date, despite France’s recent history of record-breaking heat waves. Historical data shows June highs in Paris typically range from 20°C to 24°C, rarely exceeding 29°C, though the country shattered its all-time record in 2022 with 45.9°C at Gallargues-le-Montueux [3]. Even Paris itself recorded 42.4°C on 25 July 2019, proving extreme heat can strike the capital [7]. The consensus is heavily contrarian, betting against any heat spike, but value may lie in the underdog position if atmospheric models shift toward a Mediterranean heat dome.

Traders must monitor the European Centre for Medium-Range Weather Forecasts (ECMWF) and Met Office updates for any sudden pressure anomalies or southerly wind flows that could transport hot air from the Sahara. A recent AP News report highlighted how an early heat wave gripped Europe in 2022, closing the Eiffel Tower and Louvre due to temperatures exceeding 44°C [2]. The key dependency is the timing of the jet stream; if it stalls north of France, a stagnant high-pressure system could trap heat over Paris. Watch for official red heat alerts from Météo-France, which have been issued repeatedly during recent summers as temperatures climb [8]. If models indicate a 30°C+ day, the 0% probability becomes a clear mispricing, offering a contrarian entry for the underdog.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Paris on June 28? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Who Will Win 2026, which mirrors the Polymarket order book at 0% fees.

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 Who Will Win 2026. 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.

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.