Highest temperature in Milan on July 21?

Platform comparison

Market context

The settlement hinges on the single highest temperature reading at Milan's Malpensa International Airport on 21 July 2026, measured in Celsius and resolved against historical Wunderground data. The 0% crowd probability suggests traders are either awaiting range options or treating this as a placeholder market awaiting meaningful price discovery.

Milan's July climate sits firmly within the Mediterranean summer pattern, with average highs around 28–30°C and extremes regularly exceeding 32°C. The city experienced a peak of 37.1°C in July 2022 and 36.5°C in July 2023, establishing that temperatures in the mid-to-high 30s are neither rare nor exceptional for this calendar date. Malpensa, situated northwest of the city centre, typically records slightly cooler readings than central Milan due to its proximity to the Ticino River valley, though the differential rarely exceeds 1–2°C. Historical volatility across July decades shows that single-day highs between 30–35°C account for the majority of outcomes, with excursions above 35°C occurring in roughly one year in three.

European summer forecasting remains constrained at the 18-month horizon, though climate models indicate La Niña conditions may persist into mid-2026, potentially suppressing extreme heat anomalies across southern Europe. Traders should monitor spring 2026 seasonal outlooks from ECMWF and Météo-France as the settlement window approaches, as these will refine expectations around jet-stream positioning and high-pressure system intensity for late July. Any significant revision to European summer temperature forecasts between now and June 2026 will likely trigger material repricing across temperature-range markets for this period.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Who Will Win. 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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.