Highest temperature in Madrid on August 17?

Platform comparison

Market context

On 17 August 2026, Madrid's highest temperature will be recorded at Adolfo Suárez Madrid-Barajas Airport Station and measured in degrees Celsius. The market currently prices all temperature ranges at 0% YES on Polygon, meaning traders are either awaiting sufficient liquidity to establish meaningful positions or the contract has yet to attract substantive trading volume. Settlement hinges on Weather Underground's Daily Observations table rather than the Day High & Low summary, a distinction that matters when automated station readings occasionally diverge from processed forecasts.

August temperatures in Madrid historically cluster between 32–38°C, with extremes occasionally breaching 40°C during heat waves. The city experienced 40.5°C on 12 August 2022 and 42.2°C on 13 August 2003, establishing that upper-range outcomes are plausible rather than theoretical. The 0% crowd probability suggests either the market has not yet attracted sufficient capital formation or traders are treating this as a placeholder contract awaiting real-time weather pattern data closer to mid-August 2026.

Traders should monitor European summer weather systems and Atlantic pressure patterns from early August onwards. Spain's meteorological agency (AEMET) typically issues heat-wave alerts 7–10 days in advance, providing actionable signals for positioning. Recent precedent shows that Mediterranean heat domes can develop rapidly; the August 2023 European heat wave saw Spanish temperatures spike unexpectedly within 72 hours. Conditional token mechanics on Polygon allow traders to enter or exit positions as forecasts crystallise, though the current 0% pricing suggests the market awaits either initial price discovery or sufficient liquidity provision to function as a meaningful prediction mechanism.

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

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.

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.