Highest temperature in Madrid on August 7?

Platform comparison

Market context

Madrid’s highest temperature on 7 August is being priced against a market that is still effectively at the *weather-forecast* stage, not the settled-observation stage. The current crowd-implied probability of **0% YES** is much lower than the live forecast picture: AccuWeather’s Madrid monthly page shows an average August high around 31°C, while several 7 August 2026 forecasts point to a hotter day, including 36°C on EaseWeather and 37.9°C on a Madrid-focused forecast cited by Debate, with an AccuWeather warning page flagging a maximum temperature of 37°C for the wider area.[1][7][5][4]

For context, Madrid in August often sits in the low 30s, but episodic heat spikes are common and can push the airport well into the upper 30s; Reuters reported Madrid reaching 40°C during Spain’s first official heatwave of 2026 in June.[10][13] That makes a near-zero market price look conservative relative to weather-model consensus, though the exact contract pay-off depends on the highest reading at Adolfo Suárez Madrid-Barajas Airport and on the specific Celsius band containing that observation, which can differ from city-centre forecasts by a degree or two.[2][7][17]

The main catalysts are straightforward: late-morning and afternoon observations at the airport, any last-minute forecast revisions, and whether official Spanish guidance continues to show temperatures above 35°C across inland areas of the peninsula on 7 August.[8] Because the market resolves on Weather Underground’s Daily Observations table rather than the summary high/low box, traders should watch the station-level trace rather than headline app widgets, and compare it with any sportsbook-style lines or third-party forecast feeds that may still be pricing the day below the low- to mid-30s.[2][8]

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

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

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 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.