Highest temperature in Madrid on July 22?

Platform comparison

Market context

Polymarket is pricing this Madrid temperature contract as if the airport station will peak at **39°C**, with that outcome at 77% and **40°C** at 21%, so the book is already leaning towards a very hot but not exceptional finish at Adolfo Suárez Madrid-Barajas Airport.[1] Because the market settles on the highest reading reported by Wunderground for the airport station between the opening and the 12:00 UTC cut-off, traders are effectively holding conditional tokens on a single-day temperature print rather than the city-wide forecast headline.[1]

That pricing sits close to the public forecast published for Madrid today, which put the day’s maximum at **39°C**, with **0% rain** and only light cloud cover.[2] The market also rhymes with recent July heat in central Spain, where Madrid has repeatedly traded in the upper 30s and, on hotter days, around 40°C or above, so the current 0% YES on the market’s top band looks disconnected from both the live forecast and the recent heat profile in the region.[3][5]

The key catalyst for holders is whether the airport station briefly overshoots the city forecast during the afternoon peak, since the contract resolves on the highest recorded temperature, not the average or the official daily maximum at another site.[1][2] In practical terms, the trade is being settled on-chain in USDC on Polygon through conditional tokens, but the off-chain risk is all in the final Wunderground history page and any late-day spike before the settlement window closes.[1] If temperatures track the published Madrid forecast without an upside surprise, the higher bands remain the relevant ones to watch.[2]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 PolyGram. 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'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 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.