No let-up in Atlantic storms
Hurricane-force winds and flooding continue as extreme low pressure continues to dominate the North Atlantic.
It is just over a week since Storm Ciara brought widespread disruption to the United Kingdom, with winds of up to 156 kilometres per hour (97 miles per hour).
Now, another intense storm has hit Iceland, bringing winds to the southeast generally between 110 and 140km/h (68 and 87m/h), but peak winds were up to 256km/h (159m/h).
This peak wind was recorded at Hafnarfjall, just 40km (25 miles) north of the capital, Reykjavik. Lying at the tip of a peninsula, Hafnarfjall experienced enhanced winds flowing from the east, down the steep slope of the western side of the Esja mountains – this wind is just short of the highest wind ever recorded in Iceland – 261km/h (162m/h) – at Gagnheioi in January 1995.
Meanwhile, another intense low pressure centre is developing to the southwest of Iceland. This storm, named Dennis by the UK Met Office, could turn out to be one of the deepest Atlantic storms on record.
Many forecasts suggest a central pressure in Dennis of around 920 millibars, although some predictions are in the 910s. It is likely to be the second or third-deepest Atlantic low pressure system in at least 200 years.
Although stormy weather is guaranteed for Iceland, the UK, southern Scandinavia and the coastal regions of countries bordering the North Sea, the forecast detail will be difficult to assess.
This is because of a bizarre “dance” likely to take place between Dennis and its predecessor. When two intense low pressure systems become close enough, they interact according to the Fuijiwhara effect. This phenomenon was first identified by Dr Sakuhei Fujiwhara in 1921 in relation to the behaviour of North Pacific typhoons.
But it applies to any intense areas of low pressure, and it is expected that Dennis will move anticlockwise around the western low pressure centre before sweeping in towards Scotland on Sunday and Monday.