Highest temperature in Paris on July 26?

Platform comparison

Market context

The event is the highest temperature recorded at Paris–Le Bourget Airport on 26 July, and the current crowd price of 0% suggests the market is treating a materially hot reading as extremely unlikely despite midsummer climatology. July in Paris is typically warm rather than extreme, with average highs around 25°C and rainfall still common, so the baseline for this market is a moderate summer day rather than a guaranteed heat event.[1][2]

For historical framing, the key question is not the average July high but whether conditions can push the airport station into a much warmer range for a single day. Recent Paris heatwave coverage shows that the city can still experience severe spikes, with advice from weather-tracking and travel sources focusing on peak heat around midday to late afternoon, when maximums are most likely to be set.[3][4] That matters for comparing platforms: Polymarket prices this as implied probability, while Kalshi and Betfair-style books usually express the same view through decimal prices, so a 0% reading can look more dramatic than an equivalent longshot quote elsewhere.

The main catalysts are short-range forecast updates, cloud cover, wind direction, and any regional heat alerts that affect Greater Paris in the 24–48 hours before settlement. Because the market resolves from the Paris–Le Bourget Airport Station record for that day, traders should watch whether temperatures crest before noon UTC and whether the airport is materially warmer than central Paris due to local conditions. Fee structure and access also diverge by venue: Kalshi and some exchange-style platforms tend to add clearer commission or spread costs, while Betfair/Smarkets-style books may quote a tighter market but with KYC and jurisdiction limits that affect who can participate and at what size.

Sources: 1 · 2 · 3 · 4

Methodology

This page compares Highest temperature in Paris on July 26? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Robinhood Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Robinhood Prediction Markets has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.