In Pictures: Storm Dennis batters the United Kingdom
Some regions now being affected by Dennis were also hit by a preceding storm, Ciara.
Storm Dennis, one of the deepest low-pressure centres to have formed in recent years, has brought severe weather to Iceland and many western and central parts of the UK.
Some of the regions now being affected by Dennis were also hit by a preceding storm, Ciara, which brought stronger winds than Dennis but less rain. Nevertheless, rivers were already full and the ground saturated before Dennis’s arrival.
The UK Met Office warned of rainfall totals of 50 to 100 millimetres in many areas.
The military has been called in provide assistance in parts of northern England, where rivers have overflowed in recent days.
There are no reports of significant damage along the western coast although rough seas extend across much of the North Atlantic with wave heights of up to 20 metres, 300 kilometres west of Ireland, being reported on Friday.