Highest temperature in Paris on June 22?

Platform comparison

Active sub-markets

Market context

Paris’s hottest reading on 22 June will be set by the peak temperature recorded at Paris-Le Bourget Airport, so the market is really about whether the day reaches a summer high above the usual June band rather than any single forecast hour. Paris June averages are typically in the low-to-mid 20s Celsius for daytime highs, with Weather Spark showing daily highs rising from about 69°F to 74°F and only rarely exceeding 84°F, which makes very hot outcomes relatively uncommon even in late June.[2]

The current **0% YES** implies the crowd sees no realistic path to a qualifying high, but recent regional heat signals argue against treating that as a stable anchor. Reuters reported on 19 June that the French weather agency expected a significant rise in temperatures from Sunday until at least Tuesday, with peaks around 35–38C and an early-June period already reaching record-high territory in parts of France.[3] That matters because the Wunderground settlement uses the *highest* temperature for the whole day at the airport station, so an afternoon spike is enough even if morning conditions look mild.[5]

For platform context, Polymarket and Kalshi both quote the event as a binary probability, while Betfair and Smarkets usually price the same kind of weather view through exchange-style decimals, so a “0%” screen can still correspond to a thin but non-zero back price once fees and spread are considered. KYC and access also diverge: regulated books such as Kalshi and exchange venues typically enforce stronger identity checks and jurisdiction limits than crypto-native prediction markets, which can affect who is able to express a view on a Paris weather market and how quickly prices react when new French forecast updates land.[3]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Paris on June 22? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). Kalshi Alternative UK routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

FAQ

Where can I trade this market with the lowest fees?

On Kalshi Alternative UK, 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.

Is this market available outside the US?

Kalshi Alternative UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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.

What does it cost to trade on Kalshi Alternative UK?

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