Highest temperature in Paris on August 19?

Platform comparison

Market context

Paris is heading into a late-summer temperature contest with forecast highs clustered in the mid-to-upper 20s Celsius, but the range of published outlooks is wide enough to keep the exact peak uncertain before the noon UTC settlement cut-off. Recent forecasts point to a mostly cloudy day with showers or thunderstorms possible, with highs variously around 24°C to 28°C, which is consistent with a market priced at 0% for the top band only if traders expect the day to top out below the upper Celsius ranges cited by some models.

The comparative backdrop matters because Paris in mid-August often sits near the high-20s Celsius, yet short-lived showers or cloud cover can cap the observed maximum and make station-specific readings important. The contract resolves off the daily observations at Paris-Le Bourget Airport rather than a headline day-high figure, so small differences in timing, cloud breaks and convective showers can shift the recorded maximum by a degree or two. That source choice is especially relevant when the broader forecast is mixed, as current outlooks also show materially different published highs from different weather providers.

For traders, the key catalysts are the final overnight and morning updates before 12:00 UTC, because a change in shower timing or cloud cover is what would most affect the station’s maximum before settlement. Forecast services currently flag either scattered showers, isolated thunderstorms, or simply a cloudy day, so the main dependency is whether heating is suppressed early enough to hold the observed high down. In cross-platform terms, that leaves prediction-market pricing at 0% looking much more conservative than the published weather outlooks, while sportsbook-style weather lines, where available, would likely sit closer to the mid-20s Celsius consensus than to an extreme outcome.

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 Kalshi vs Polymarket, 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 Kalshi vs Polymarket. 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.