Update 6.11pm: ESB Networks has continued to restore electricity supply following Hurricane Ophelia but approximately 19,500 customers remain without supply, a number of which are due to Storm Brian.
If conditions worsen, ESB crews will have to suspend the repair effort.
"ESB Networks is acutely aware of the tremendous difficulties and frustrations of communities in areas that remain without power.
"We sincerely apologise to those affected and we ask the public to reach out to those in their communities that are without supply," it said.
Estimated restoration times are available on the PowerCheck App and on esbpowercheck.ie
Update 3.53pm: The ESB has confirmed power has been restored to North Dublin, Drogheda and Dundalk following Storm Ophelia.
The centre of Storm Brian has now passed onto Britain.
The centre of #StormBrian is now moving into Britain.
Strong NW winds and heavy showers remain across Ireland until early tonight. pic.twitter.com/Kbc5GPrBHz— Met Éireann (@MetEireann) October 21, 2017
Crews restored power to 8,000 homes and businesses yesterday with work continuing to re-connect the 22,000 customers still without electricity.
Storm Brian has hampered efforts in the worst-affected counties of Cork and Wexford.
Waterford and Wexford have now been downgraded from an orange wind warning, although it still remains in place for five coastal counties with high winds expected throughout the afternoon.
Galway, Mayo, Clare, Cork and Kerry are still on an Orange Wind Warning valid until 9pm tonight.
Earlier: Parts of the country have been affected by flooding as Storm Brian makes landfall.
In Limerick the River Shannon has overflowed with emergency crews being deployed while flooding in other areas of the south and west have also been reported.
The Orange wind warning and Yellow rain warnings remain in place.
Meanwhile, around 22,000 homers remain without electricity, a small number of which are due to Storm Brian. Customers who experience a new service interruption should report it on esbnetworks.ie or call 1850 372 999.
In a statement, ESB Networks said: "A Met Éireann Status Orange wind warning has been issued for seven coastal counties, including Cork and Wexford, (and this will) hamper restoration efforts.
"Should the weather conditions worsen further, our crews will be stood down until it is safe to resume repairs again. Winds speeds up to 130 km/h will cause outages to customers in Mayo, Galway, Clare, Kerry, Cork, Waterford and Wexford today."
Cork County Council has asked members of the public to avoid coastal areas and exercise extreme caution while driving.
All the county's public water supply schemes are back in action after the outages caused by Ophelia.
In Cork city:
Due to damage caused to footpaths, trees and roads around Pairc Ui Chaoimh during Storm Ophelia, fans are being advised to arrive early for the Cork hurling and football finals tomorrow, park in the city or the Boreenmanna Road.
Pedestrians are advised to walk to the grounds via Monahan Road as Centre Park Road is currently closed to pedestrians or via Maryville.
In relation to roads in Cork county:
Cork County Council’s 24 hour incident number 021 4800048 is open and will remain so throughout the weekend.
The Council will continue to monitor the situation over the coming hours. Any developments will be posted on the Council's website, as well as on the Council's Facebook and Twitter account.
Storm Brian brings wind and rain to south and west; whole country will be affected later
Members of the public have been urged to heed safety warnings as Storm Brian approaches from the Atlantic.
The eye of the storm is passing over the country this morning. Met Éireann is warning that some flooding is expected, especially in coastal regions where very high seas are also forecast.
Orange level wind warnings are in effect for coastal counties to the south and west, with very strong winds this morning, while a yellow rainfall warning has also been declared for those areas.
In the afternoon, strong to gale force northwest winds will develop countrywide with severe gusts around coasts. Heavy showers or longer spells of rain, with thundery downpours, will continue to occur across the country. Top temperatures of 13C or 14C are forecast.
Tomorrow will bring better weather, with bright spells and scattered showers. However, rain will spread from the Atlantic during the afternoon and evening.
It is thought the storm's progress may affect efforts to re-connect the 36,000 customers who are still without power following Hurricane Ophelia.
Derek Hynes from ESB Network has thanked customers for their patience and pledged that no one will be left behind.
He said: "We'd like to thank everybody who heeded the warnings, who phoned us at 1850 372 999 and who put information into our website to give us locations and details about fallen wires and unsafe situations."
On this occasion, the National Emergency Coordination Group (NECG) said Brian does not present exceptional public safety issues.
Sean Hogan from the NECG said: "The OPW (Office of Public Works) has been monitoring river and coastal areas and while the situation in some urban areas is being kept under review, there is no expectation of major flooding.
"Some minor works are taking place in some more predictable areas in Cork and Limerick where flooding may take place and the Defence Forces are assisting in Limerick."
The Irish Coast Guard's Gerard O'Flynn says rough seas and extreme weather might look exciting but getting too close can be risky.
""The timing is unfortunate. It's bad winter weather, but hopefully won't be as mad as Monday (when Ophelia struck)," he said.
"For anyone who's going near the sea, our advice is to stay back, stay dry and stay high. If you do see somebody in trouble, don't hesitate to dial 112 and ask for the Coastguard."