Hundreds of people have been left without power after high winds with gusts of up to 140km/h swept across Ireland, causing outages in many parts of the country.
ESB crews are currently working to restore power for about 500 customers in Cavan, Longford, Mayo, Sligo and Donegal this evening. A further 2,000 customers in Dublin and Meath were also without power earlier today due to a failure in Coolmine.
Gardaí warned people not to travel unless absolutely necessary. It will remain very windy tonight with strong and gusty westerly winds persisting, but there will be a slight reduction in wind speeds.
AA Roadwatch warned motorists to be extremely vigilant if driving in high-sided vehicles and on exposed roads. Exceptionally high seas along the western seaboard, in conjunction with high spring tides, may cause coastal flooding in some areas.
Trees were brought down in Galway city and county while high tides made worse by the gales caused severe flooding along the promenade in Salthill. In Clare, the Cliffs of Moher visitors' centre urged people to postpone planned trips to the site while in Limerick flying debris was making driving conditions dangerous.
Road travel in counties Cork, Tipperary, Donegal, Galway and Kildare was also disrupted by fallen trees and branches and flooding.
The Road Safety Authority is also advising motorists to take care and allow extra distance between vehicles. Drivers of HGVs, buses and any other large vehicles are warned to be particularly careful as they are more at risk in strong winds due to the height of their vehicle.
Vulnerable road users such as pedestrians, cyclists and motorcyclists are advised to check local weather forecasts before making journeys and, if necessary, consider delaying journeys until conditions improve.
A number of ferry services between Ireland and the UK were cancelled yesterday and today. Flights are operating as normal.
Earlier today, Dart services operating between Bray and Greystones and Pearse were limited due to damage to overhead power lines. Services were also briefly suspended between Howth and Howth Junction.
In Co Donegal, many trees have been uprooted and telegraph poles blown down. Several events had to be cancelled as organisers aired on the side of caution,
However, organisers of the famous Glenties Harvest Fair decided to battle on despite the storm with one large tree being blown down outside the town. Dozens of stallholders, who normally throng the streets of the town, were forced indoors to the town's community centre. Organisers of a huge charity golf ball drop, which was due to take place at Letterkenny Town Park, were forced to cancel the event.
Local ferry services to and from the islands off the county were cancelled for the day.
Meanwhile, weatherman John Eagleton was forced to apologise to thousands of people across Donegal after he got the outcome of Hurricane Katia wrong.
The well-known forecaster told listeners to Highland Radio at 10.15am that winds had peaked. But Mr Eagleton was forced to come back on air and apologise when power was knocked out to thousands of homes – including the radio station on which he made his prediction.
Katia is the second major hurricane of the 2011 Atlantic hurricane season and was rated as a category four hurricane on the Saffir-Simpson hurricane scale at its peak. The scale rates hurricanes from one to five, with five being the strongest.
Parts of the UK were also battered by the bad weather today with warnings that Scotland, Northern Ireland and parts of northern England and Wales could see trees brought down by with gusts of up to 120km/h expected in the region.
Flooding alerts have been issued along the North Sea coast in Yorkshire and the west coast of Anglesea.