Highest temperature in Paris on May 31?

Platform comparison

Active sub-markets

Market context

On 31 May 2026, the highest temperature recorded at Paris-Le Bourget Airport will fall into one of several defined ranges. This market settles based on historical weather data from Wunderground, the same source used across most major prediction platforms, though settlement timing and fee structures vary significantly between books. Polymarket charges a 2% taker fee and operates without KYC for most users, whilst Kalshi enforces full identity verification and applies a flat fee model that can favour larger positions. Betfair and Smarkets use decimal odds rather than implied probability displays, which can obscure the true cost of entry for traders unfamiliar with that convention.

Late May in the Paris region typically sees temperatures between 20–25°C, with occasional warm spells pushing into the upper 20s. Historical data from the past decade shows that extreme heat events—temperatures exceeding 30°C—occur rarely in late May, though the 2022 European heatwave demonstrated that early-season temperature anomalies are possible. The current 0% implied probability on this market likely reflects base-rate expectations rather than any specific forecast, and traders should cross-reference Météo-France's seasonal outlook and European medium-range forecasts closer to settlement.

Traders monitoring this market should track European weather pattern shifts in April and May 2026, particularly any persistent high-pressure systems over continental Europe. The UK Met Office and ECMWF issue extended forecasts 10–15 days ahead; anomalies in those models during late May will be the primary catalyst for probability shifts. Settlement occurs at 12:00 UTC on 31 May, giving traders a narrow window to adjust positions based on morning observations from Le Bourget.

Methodology

We read Highest temperature in Paris on May 31? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live quote comes directly from the Polygon order book; the other three are listed with their platform attributes — fees, KYC, settlement currency, payment options — because a 1:1 contract comparison without API access would be guesswork.

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). Polymarket Alternative UK routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

FAQ

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 Polymarket Alternative UK?

Zero. Polymarket 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.

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.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Polymarket Alternative UK triggers a quick verification flow that finishes in 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.