Highest temperature in Paris on May 23?

Platform comparison

Active sub-markets

Market context

On 23 May 2026, the highest temperature recorded at Paris-Le Bourget Airport will settle this market into one of several temperature bands. Polymarket currently prices all outcomes at 0% YES, reflecting the settlement window's distance and the inherent difficulty in pricing weather events eighteen months forward. The contract uses USDC on Polygon, with conditional tokens representing each temperature range; whichever band captures the actual high temperature that day will resolve to 1.0, whilst all others expire worthless.

Historical May temperatures at Le Bourget show considerable variability. The station's records indicate May highs typically range between 18°C and 26°C, though extremes have reached 30°C during warm springs. The 2022 heatwave pushed May highs to 28–29°C across northern France, whilst cooler years saw maxima below 20°C. This historical spread explains why traders cannot anchor on a single expected outcome; the market's current flat pricing reflects genuine uncertainty about whether May 2026 will track towards the cooler or warmer end of the seasonal range.

Traders monitoring this contract should track European seasonal forecasts as spring 2026 approaches, particularly from Météo-France and the European Centre for Medium-Range Weather Forecasts. Atlantic pressure patterns and North African heat advection typically drive May temperatures in the Paris region; any signals of a persistent high-pressure system or early summer heat dome would shift probability towards higher temperature bands. The resolution source, Wunderground's historical data for LFPB station, is publicly accessible and updates daily, allowing traders to calibrate positions as the settlement date draws nearer.

Methodology

We track Highest temperature in Paris on May 23? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Is this market available outside the US?

PolyGram 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 PolyGram?

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

Do I need to KYC for this market?

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