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Once again, Portugal and Spain find themselves recovering from significant flooding following Tempest Claudia brought torrential downpours and powerful gusts the previous week.

Claudia's Genesis and Journey

The storm system formed from a region of depressed atmospheric pressure that had earlier caused early season freezing temperatures and snowfall through the eastern regions of the Canadian territory and the north-eastern United States at the start of November.

This storm tracked eastwards across the Atlantic Ocean during the second weekend of November before slowing and stalling to the north-west of the Spanish and Portuguese landmass, caught in the trough of an ever more meandering atmospheric river.

Impact on Spain and Portugal

The northwestern Spanish region of Galicia was initially impacted, with a substantial 80 to 150 millimetres of rain falling along its western coastline in just 24 hours up to the evening of Wednesday as a sluggish front of rain drifted across western parts of the region.

Additional rainfall and electrical storms on Thursday led to floods to parts of Portugal where a senior pair perished in the city of Lisbon after floodwaters from the swollen Tagus invaded their residence as they slept.

Unsettled atmospheric states continued into the weekend, with a twister ripping through a outdoor lodging area and a nearby hotel in the town of Albufeira in southern Portugal on Saturday, claiming the life of an British woman aged 85 and injuring 28 people.

Extended Consequences across Europe

Claudia had wider effects across western Europe. By pulling tropical air from the subtropical zones, the system helped temperatures in France's south-west to 29.8C (85.6F), the nation's all-time high late autumn reading.

By last Friday, this tropical air mass collided with a cold air mass across the northern areas of Europe, forming a precipitation zone extending from the west of Ireland to the Russian Federation.

In the United Kingdom, this stationary front of rain produced record-breaking rain accumulations, resulting in major inundations in Wales.

As Claudia progressively weakens at the start of the week, the chilly atmospheric system will move towards the south, delivering to Europe its initial glimpse of the winter season.

Parallel Events in the state of California

The Golden State underwent a plume of tropical moisture last week, causing torrential rain and powerful winds that resulted in sudden inundations and debris flows in regions impacted by blazes previously in the year.

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

Over four inches of rain accumulated over coastal parts of southern California in aggregate, hitting 200mm overall in spots on high ground.

Such a weather system is a plume of tropical, saturated air stemming from the tropics or subtropics.

Burn scar areas including the Pacific Palisades area and Altadena endured the most intense the rapid inundations and landslides, leading to evacuations.

In other parts of the state, a man in his seventies died after his vehicle was carried away from a flooded bridge, and a seven-year-old girl and her father were pulled into the Pacific by big swells on the California's Central Coast.