🔗 Share this article

Portugal and Spain are once more dealing with the consequences of significant flooding after Storm Claudia delivered heavy rain and powerful gusts over the past seven days.

Claudia's Formation and Trajectory

The storm system developed from an area of low pressure that had previously caused unseasonably early cold and snowy conditions through eastern parts of Canada and the American north-east in early November.

The system tracked eastwards across the Atlantic Ocean during the second weekend of November before slowing and stalling to the northwestern area of the Iberian region, caught in the trough of an ever more meandering atmospheric river.

Impact on Iberia

The northwestern Spanish region of Galicia was the first affected, with a substantial 80 to 150 millimetres of rain falling along its Atlantic coast in just 24 hours up to Wednesday night as a sluggish front of rain pushed across western parts of the peninsula.

More downpours and stormy weather on Thursday brought flooding to Portuguese localities where a senior pair perished in Lisbon after floodwaters from the swollen Tagus flooded their dwelling as they rested.

Unsettled atmospheric states persisted into the weekend, with a violent whirlwind tearing through a outdoor lodging area and a nearby hotel in Albufeira in the Algarve region on Saturday, killing an British woman aged 85 and harming 28 people.

Extended Consequences across the European continent

The storm produced more extensive impacts across western Europe. By drawing warm air from the subtropics, the system contributed to thermometers climbing in south-west France to nearly 30 degrees Celsius, the nation's all-time high autumn temperature.

By Friday, this hot and moist atmospheric body clashed with a frigid air system across more northern parts of Europe, forming a precipitation zone extending from Ireland's west to Russia.

In the Britain, this halting system of rain delivered exceptionally large precipitation amounts, resulting in significant waterlogging in the Welsh region.

As Claudia continues to weaken at the start of the week, the chilly atmospheric system will push south, giving Europe its initial glimpse of winter.

Related Incidents in the state of California

The US state of California encountered a so-called atmospheric river the previous week, delivering heavy rain and strong winds that provoked rapid flooding and mudslides in zones affected by wildfires in the recent past.

In excess of 50 millimetres of rain poured down in the southern region of the state on the week's end, with a another 50 millimetres across extensive areas of California on Saturday.

Over four inches of rain fell over shoreline regions of the state's south in total, hitting 200mm overall in spots on high ground.

Such a weather system is a narrow band of tropical, saturated air originating from the tropics or subtropics.

Burn scar areas including Pacific Palisades and Altadena experienced the worst of the rapid inundations and mudslides, prompting evacuations.

In other parts of the state, a elderly male passed away after his automobile was washed off a inundated overpass, and a young girl aged seven and her father were dragged into the Pacific by big swells on the California's Central Coast.