Latest news with #rollcloud
New York Times
14 hours ago
- Climate
- New York Times
Clouds Are Cool, but Have You Ever Seen One Like This?
The dramatic mass moving ashore one afternoon in Portugal this week looked like something out of a movie: dozens of people who had gathered at a beach to escape an oppressive heat wave stared up at the sky as it inched toward them. Was an alien ship about to emerge? Should someone call Jeff Goldblum? But it was a cloud that stopped people in their track — a 'roll cloud,' to be specific, which more typically form from thunderstorms. In this case, the cloud formed at the intersection of the ocean and the land as a cool, moist air mass moving over the Atlantic Ocean collided with dry, hot air over southwestern Portugal, which, like much of Europe, has been sweltering in a weeklong heat wave. The roll cloud is created by a wave in the atmosphere that causes a rising and sinking motion over adjacent areas, allowing the clouds to form and appear to roll forward. You can see that below in an aerial image, where the crest and trough of the cloud are visible and resemble an ocean wave. Sean Waugh, a severe storms expert with the National Severe Storms Laboratory who typically encounters such clouds as thunderstorms move over the Plains in the United States, compared the clouds to what happens when a rock is dropped in a pond. The cloud is just the leading edge of a ripple in the atmosphere. While the cloud in Portugal occurred in the afternoon, it was most likely a 'morning glory,' a specific type of cloud often associated with roll clouds that more commonly occurs after sunrise in the Gulf of Carpentaria in Australia. This type of roll cloud can stretch many hundreds of miles long, which is why it was seen up and down much of the central coast of Portugal. The heat wave that has swept Europe this week has led to multiple deaths and helped fuel wildfires in Greece, Turkey and Portugal. High temperatures are expected to spread east in the coming days. Tracking Heat Across Europe See detailed maps of the latest temperature forecasts across Europe.
Washington Post
2 days ago
- Climate
- Washington Post
Rare ‘roll cloud' delights Portuguese beachgoers amid record heat wave
As much of Europe battled a rare heat wave, beachgoers trying to cool off on the coast of Portugal were stunned by another surprising weather phenomenon. Videos taken across parts of the northern and central coast showed a dark, tsunami-like cloud formation, commonly referred to as a roll cloud, billowing over the ocean, stretched out across the horizon, on Sunday. Beachgoers could be seen scrambling to film the sight, or standing along the shoreline admiring the towering clouds.
Fox News
3 days ago
- Climate
- Fox News
Rare 'tsunami' roll cloud hovers over beachgoers in popular destination spot
A rare weather sighting occurred in Portugal as tourists and locals witnessed a one-of-a-kind cloud in the sky in recent days. (See the video at the top of this article.) A "tsunami" roll, also known as a roll cloud, filled the sky on Sunday following a heat wave, according to Euro News. Portugal's temperatures hit over 107 °F with heavy rain, thunderstorms and hail. The roll sits low in the sky in a horizontal tube-shaped arcus cloud and is "relatively rare," according to the National Weather Service (NWS). "Roll clouds usually appear to be 'rolling' about a horizontal axis, but should not be confused with funnel clouds," said NWS. Stephen Corfidi, a meteorologist at the National Oceanic and Atmospheric Administration (NOAA), previously told National Geographic the clouds are typically associated with thunderstorms. Roll clouds "can last for several hours and extend for several hundred miles," Corfidi told the outlet. "The 'shear' across the inversion sets up a rolling motion much like that of a rolling pin used in a bakery," said Corfidi. Beachgoers took to social media to share videos and discuss the phenomenon. "It was nuts to have experienced this rolling cloud in the north of Portugal. Felt like a tsunami out of a movie," said one X user. Another user wrote, "This cloud rolled in like an actual tsunami over Portugal." "Looks scary, but cool," posted an X user. A user added, "This does look fricking cool, tbh."
The Independent
3 days ago
- Climate
- The Independent
Rare weather phenomenon grips Portugal beach during heatwave
This is the moment a rare phenomenon was spotted at a beach in Portugal, as the country faces a heatwave with highs of 42C. Beachgoers on Sunday (29 June) were shocked when they saw a 'roll cloud' coming out of the ocean and heading towards the shore. The dense tsunami-like cloud occurs when hot and cold air masses collide, forming a thick cloud that condenses into a curved-shape. Climate expert Mário Marques said it is not the first time Portugal has experienced a roll cloud, but is more common to witness the phenomenon in somewhere like Australia, where cold air from Tasmania collides with hot air on the mainland.
BBC News
3 days ago
- Climate
- BBC News
Weird cloud in Portugal looks like humongous wave
Watch as this rare weather phenomenon rolls in from the sea at a beach in relaxing on Furadouro beach, south of the city of Porto, saw a huge cloud rolling in from over the the cloud looked like a giant wave heading towards them, it was nothing to worry about for those on the beach. While some sunbathers got up and moved away, others stayed and were caught in breezy and blustery conditions as the cloud passed overhead. Portugal is in the middle of a heatwave with highs of 42C and the conditions are likely to have been the cause of the strange cloud. "This is a spectacular example of a roll cloud. It's a type of arcus (curved) cloud that can form near to a powerful thunderstorm," said Sarah Keith-Lucas from BBC Weather. "Cool moist air from over the ocean rolls in to meet the warm, dry air over land," added Sarah, explaining that the heat it can cause water in the air quickly to turn into tiny droplets which forms a cloud. "Due to air flowing in different directions above and below the cloud, it can form into the distinctive cigar shape - a long, thin cloud which is most common close to the coast."
