Overview

• IPMA confirmed via satellite that the roll cloud formed between Peniche and Póvoa do Varzim around 5–6 p.m. local time on July 1
• Meteorologists say the phenomenon arises when cooler marine downdrafts undercut warm, moist air to create a horizontal, tube-shaped arcus cloud
• The viral video shared by X user ‘Volcaholic’ has topped 20,000 views as beachgoers captured sudden gusts accompanying the cloud’s advance
• Mainland Portugal has seen record highs above 40 °C, prompting the National Civil Protection Authority to issue maximum wildfire-risk warnings
• Observers reported the cloud stretching roughly 150 km along the coast from Figueira da Foz to Vila do Conde, underscoring its unusual scale