Highest temperature in Milan on July 31?

Platform comparison

Market context

Milan’s deciding temperature for this contract will be the day’s high at Malpensa Airport, not the city-centre reading, so the key question is whether the airport station gets above the low-30s Celsius before the settlement window closes at 12:00 UTC. July in Milan is normally hot enough that a low-30s print is routine: long-run climate pages put typical July highs around 29–31°C, and recent monthly forecasts for 31 July have clustered near 31°C to 31.7°C, with AccuWeather showing about 85°F/29.4°C to 87°F/30.6°C depending on the Milan station page.[1][2][10][14]

That backdrop helps explain why a 0% YES implied probability looks more like a pricing artefact than a genuine view that an Italian summer high is impossible. The market is also much narrower than a citywide temperature bet, because Malpensa can run slightly cooler than central Milan and the contract resolves only to the highest temperature recorded during the specified daytime window, which can leave room for a one-or-two-degree miss if cloud cover or storm outflow caps the afternoon peak.[10][15][19] Recent reporting on Milan’s extreme heat has shown that the city can reach record territory during summer heatwaves, reinforcing that upper-30s Celsius outcomes are not implausible in the right pattern, even if they are far from guaranteed.[15]

For traders, the main catalysts are the short-range forecast updates, any heat advisories or thunderstorm warnings for Lombardy, and the exact timing of the day’s warmest air relative to the 12:00 UTC cut-off. In practical terms, the market is most sensitive to whether the synoptic set-up favours a clear, drying afternoon versus a more unstable, storm-prone one; once morning clouds, rainfall, or frontal passages are evident, the odds of a higher daily maximum fall quickly, while a persistent hot ridge would keep the distribution skewed towards the low-30s Celsius.[7][12][19]

Sources: 1 · 2 · 3 · 4 · 5

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

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?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 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?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.