Highest temperature in Madrid on June 29?

Platform comparison

Market context

The underlying event is the peak of Spain’s historic June 2026 heatwave, which has already pushed temperatures above 110°F (43°C) in parts of the country and triggered the nation’s first official heatwave of the year. On 21 June, Madrid recorded highs of 40°C (104°F), and by 24 June, the country had shattered two June temperature records, with average daily temperatures reaching 28.17°C—beating the 2025 benchmark of 28.01°C[5][7]. This extreme context frames the current 0% crowd-implied probability for the market: traders are effectively betting that the 29 June peak at Barajas Airport will not exceed the upper bounds of the resolution range, likely because the heatwave’s intensity is already being absorbed into the market’s baseline expectations.

Historical June data shows Madrid’s daily highs typically climb from 78°F to 88°F (25.5°C to 31.1°C), rarely exceeding 96°F (35.6°C)[2]. However, 2026 has broken this pattern: temperatures in excess of 110°F (43.3°C) were forecast for 23 June, and Seville reached 36°C (97°F) during the same period[3][1]. The market is leaning on the catalyst of the heatwave’s continuation, with no scheduled cooling events or major weather disruptions announced for 29 June. Traders should monitor updates from the US Embassy’s weather alert system and Reuters’ real-time heatwave coverage, as both sources have confirmed the persistence of extreme conditions across central Spain[3][5]. With the settlement window ending 2026-06-29T12:00:00Z, the market’s outcome hinges on whether Barajas Airport records a temperature within the resolution range during the peak afternoon hours (2–5 PM), when heat intensity is strongest[1].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Political prediction markets differ structurally from sports betting: thinner liquidity, longer settlement windows, higher sensitivity to single news events. This page shows the live Polymarket quote for Highest temperature in Madrid on June 29? plus platform attributes for the three reference venues, so you can see at a glance where the deepest market for this question sits.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

FAQ

How accurate are political prediction markets?

Historically more accurate than polls. Polymarket's Brier score on US 2024 elections was ~0.11 — better than 538 (~0.14) and every mainstream poll. Markets aggregate information with real skin in the game.

What resolution source is used for elections?

Polymarket defines the source per contract — usually Associated Press (AP Race Call), Reuters or the official electoral commission. The source is stated in contract details before the market opens.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Are political prediction markets legal in my country?

It varies. They sit in legal gray areas in most jurisdictions. Polymarket is geo-blocked from US/UK/EU; some broker frontends have a different geo footprint. Trade only with capital you can afford to lose, and only if you understand the legal status in your jurisdiction.

Which political events have the biggest volume?

US Presidential election, party nominations (DNC/RNC), Senate majorities, individual state outcomes (Pennsylvania, Michigan, Wisconsin), and major European elections. Peak markets reach $50-500M per event.