Highest temperature in Paris on August 9?

Platform comparison

Market context

Paris is priced as a **heavy underdog to a very hot outcome**, with the crowd-implied probability of **1% YES** implying the market is broadly sceptical that the highest temperature at Paris-Le Bourget Airport on 9 August will land in a comparatively high range. The consensus sits firmly on the cooler or middling bands, while the value question is whether late-summer heat can push the day’s peak above the market’s current expectations. Forecasts for Paris around this period point to daytime highs near **30°C** or a touch above, which is consistent with a market leaning away from an extreme top-end reading.[12][14]

Historical and comparable cases argue for caution before fading the warm side too aggressively. Paris in August often sits in the upper 20s to low 30s Celsius, and recent market behaviour in the same city has shown a strong tendency to concentrate around a single outcome when the forecast is clear; for instance, a sibling market on 8 August was already fully priced to one band at 100%.[1][15] That makes the current 1% YES look like a contrarian longshot rather than a balanced book, but it also leaves scope for sharp repricing if the observed daily maximum at Le Bourget trends a few degrees hotter than the forecast median.

The main catalysts are the official short-range forecasts and any late-day updates on cloud cover, showers, or convective heat build-up, because the market resolves off the **Daily Observations** table rather than the summary high/low display. Time and Date’s outlook for Sunday shows **90°F/63°F** with late showers and cloud, while Paris forecast pieces for the same weekend call for temperatures around or above **30°C** and possibly hotter, with another heatwave then building into the following week.[12][13][14] For a handicapper, that keeps the favourite side with the cooler bands, but any evidence of sustained sunshine and suppressed rainfall would be the clearest underdog/value angle for a higher recorded maximum.[12][14]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Who Will Win 2026, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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.

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 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.