Persistent high-pressure systems and above-average baseline temperatures across central Spain—following the hottest first half of 2026 on record and a late-June heatwave that pushed Madrid to 40°C—have driven market-implied odds toward 39–40°C for July 6. Official forecasts from AEMET, Met Office, and BBC currently converge on daytime maxima of 38–39°C under mostly clear skies and light northeasterly winds, with limited model spread on peak values. The narrow edge for 40°C reflects trader expectations that urban heat-island amplification or minor forecast upgrades in the final 48 hours could nudge readings one degree higher, while lower outcomes remain possible if subsidence weakens or boundary-layer mixing increases. Resolution hinges on the official daily maximum recorded at Madrid’s reference station.