Hurricane-force winds up to 80 knots (92 mph) and monster waves that could reach over 100 feet (30 meters) high were roaring across North Atlantic, the U.S. National Weather Service's Ocean Prediction Center reported early Saturday.
Heavy rain and strong winds are moving across Britain, and are expected to afflict all parts of the country, including areas of northern England already suffering from last weekend's storms. The peak disruption is set to take place later Saturday.
The fourth storm of the winter season, dubbed Dennis, is already causing widespread travel disruptions. Airlines have pre-emptively canceled hundreds of flights out of London and other U.K. airports and train lines have warned about possible delays and cancellations. Tens of thousands of passengers will be affected on what is a busy travel day for families as most schools in the country close for a one-week mid-winter break.
Areas in northern England, which are still recovering from Storm Ciara weekend, face up to 4 1/2 inches (120 centimeters) of rain. The country's Environment Agency said flooding is likely to be worse than during last weekend — when hundreds of homes were flooded — since the rain will be falling on already saturated ground.
Britain's Met Office has issued a number of weather warnings covering most of the country.
A Royal Navy ship was helping a search-and-rescue operation off the coast of Margate in southeast England after a man was reported to have fallen overboard from a vessel.
Easyjet has already cancelled around 230 flights in and out of the country as wind speeds are set to hit 70 mph (113 kph). British Airways has also cancelled flights.
British army personnel are set to provide support for stretched communities in the flood-hit Calder Valley region in West Yorkshire.
"This extra and expert resource couldn't be more welcome to support already exhausted communities and help us respond to further weather warnings across Calderdale," said local council leader Tim Swift.
Storm Ciara killed eight people across Europe, two of them in the U.K.