Key points
- Dramatic cloud formation surprises beachgoers with strong winds
- Roll clouds form when hot and cool air collide
- Portugal faces extreme heat, storms, and wildfire warnings
ISLAMABAD: A dramatic video capturing a rare “roll cloud” over a beach in Portugal is going viral on social media, leaving viewers captivated. According to EuroNews, the phenomenon occurred on Monday while the country was enduring an intense heatwave.
The unusual cloud formation appeared over several beaches along Portugal’s coastline.
This rare meteorological event happens when air masses of differing temperatures interact with sea breezes, forming a dense, tube-shaped cloud that moves horizontally. Though it resembles a massive wave, it bears no relation to tsunamis.
Footage of the occurrence has surfaced online, showing a thick cloud rolling in from the sea towards the beach. As the formation nears the shore, strong winds follow, catching beachgoers off guard.
Since being shared, the video has attracted over 20,000 views and numerous likes.
Bringing relief
“Holy cannoli! Is this the storm front that will finally bring relief from the heatwave?” one user asked. Another added, “It’s fascinating—these used to be common here in Northern Portugal back when my parents were young in the 60s and 70s, but disappeared until now.”
“Wow, it’s like a wave!” wrote a third. “So ominous-looking!” another commented.
A roll cloud is a low-lying, horizontal, tube-shaped cloud belonging to the arcus category and is relatively rare. It typically appears to rotate along a horizontal axis. Such clouds usually form along the edge of a thunderstorm when cooler air pushes into warmer, moist air feeding the storm system.
Risk of wildfires
According to EuroNews, this rare cloud developed during a period of extreme heat across mainland Portugal. On Sunday, the heatwave also triggered various unusual weather events, including sudden rain, intense thunderstorms, and hail—mainly affecting the country’s interior.
As temperatures continue to rise this week, the National Civil Protection Authority has issued warnings to the public, including preventative advice.
The agency has rated the risk of wildfires as “Very High” to “Maximum” in northern and central inland areas, as well as the Algarve.
