Around 400 homes in Northern Ireland are still without power as a result of heavy snow and high winds.
Northern Ireland Electricity said its engineers worked through the night to restore the supply to another 1,500 homes.
It is also using a helicopter to check lines in the most hard-to- reach places still affected in the Newry and Downpatrick areas.
Aer Lingus has cancelled a number of flights for tomorrow due to continuing bad weather in the UK.
Snow in the London area has lead to ten flights being cancelled to and from Heathrow.
They involve Dublin, Belfast, Shannon and Cork airports.
All airports across Ireland are open, but passengers flying to and from London's Heathrow with a number of airlines have had their flights cancelled.
Up to 100 flights have been cancelled at Heathrow, including two British Airways flights from Dublin this morning.
Aer Lingus and Ryanair are advising intending passengers to check with their airlines before departure.
Belfast International Airport is open and operational with only a few minor delays, while George Best Belfast City Airport is also open.
Motorists in Ireland are advised to drive with care as snow is forecast in the northern half of the country.
Gardaí said a number of cars are stuck in the snow on the Sally Gap in Co Wicklow and have asked motorists to use an alternative route.
Wicklow's mountain rescue teams attended five call outs in the past 24 hours to rescue people stranded in their cars.
Met Éireann is forecasting snow and freezing conditions in the north, northwest and northeastern parts of the country overnight.
Temperatures are expected to drop to -4 Celsius with a widespread severe frost and patches of freezing fog.
Heavy rain overnight has caused flooding in some areas.
AA Roadwatch says some roads are impassable in Co Wicklow due to flooding: the Wicklow Gap and Sally Gap; the slip road onto Old Connaught Avenue in Bray; Garden Village Avenue in Kilpeddar; Wentworth Place; and Deputy’s Pass on the Rathdrum / Glenealy Road.
Wicklow's mountain rescue teams attended five call outs in 24 hours to rescue people stranded in their cars.
Motorists in Co Kildare are advised to drive with extreme care on the N7 Dublin/Limerick Rd at J6 Castlewarden due to surface water.
Disruption in Britain
Britain faces a weekend of travel disruption as heavy snow that blankets much of the country turns to ice.
Hundreds of passengers were left stranded yesterday as airports across the UK suspended flights, and motorists struggled through blizzards along treacherous roads.
British Airways last night apologised to people trapped on planes in appalling weather at Heathrow Airport as they waited for a slot to take off, and hundreds of others had flights cancelled.
More than 400 flights were cancelled at the airport, and hundreds of people spent the night on the floor as they waited for flights to be rescheduled.
Following a joint decision by Heathrow, airlines and air traffic control, the flight schedule at Heathrow tomorrow will also be reduced in an effort to minimise the expected disruption caused by snow and low visibility.
The flight schedule will be reduced by 20% and details of which flights will be cancelled will be announced by airlines when they have finalised their schedules, a statement said.
Stansted and Gatwick airports are both operating as normal today.
The arctic blasts forced nearly 2,000 schools to shut their doors.
AA in Britain said people are likely to see dangerous driving conditions throughout the weekend as the snow compacts down and turns icy.
Snow fell across much of the UK yesterday, with south Wales experiencing the worst of the weather.