Update 9.12pm: ESB Networks have restored power to a further 8,000 homes bringing the number of customers without supply down to 29,000.
The electricity supply company said Storm Brian will hamper restoration efforts.
A status orange wind warning for the coasts of Mayo, Galway, Clare, Kerry, Cork, Waterford and Wexford is in place from 10pm tonight for a period of 24 hours.
"Southeast winds of mean speeds 55 to 65km/h with gusts of 90 to 110km/h, will veer west or northwest and strengthen further during the night, reaching orange level with mean speeds of 65-80 km/h with gusts 110-130 km/h," according to Met Éireann.
"Winds will ease to yellow warning level during Saturday evening."
Update 5.47pm: Approximately 37,000 customers are still without electricity supply following Hurricane Ophelia, according to ESB Networks.
The electricity supply company said Storm Brian will hamper restoration efforts.
It said 348,000 customers have already been re-connected.
"ESB Networks will continue restorations to every last family, farm and business until their lives are back to normal," it said.
"If you come across fallen wires or damaged electricity network, never, ever touch or approach these as they are LIVE and extremely dangerous. Please report any damage to electricity infrastructure by calling 1850 372 999," it added.
Iarnród Éireann has announced delays to Intercity services due to Storm Brian related speed restrictions tomorrow.
There will be no services on Limerick Junction to Waterford, Limerick to Ballybrophy via Nenagh
Delays of 15 to 30 minutes are expected from the first trains on the following routes: Tralee to Mallow; Cork to Dublin; Waterford to Dublin; Rosslare Europort to Dublin.
Delays are also expected from midday until further notice on these routes: Limerick to Limerick Junction; Limerick to Galway; Galway to Dublin; Westport to Dublin; Sligo to Dublin.
The delays are due to precautionary speed restrictions of 50mph to ensure safety on the railway lines.
Service information will be updated at www.irishrail.ie and on twitter @irishrail .
Iarnród Éireann apologised for the inconvenience caused.
Shannon Airport has issued precautionary advice to passengers travelling to the airport.
A spokeswoman for the airport said: “Shannon Airport is fully operational and we are continually monitoring weather conditions. As a status orange wind warning is in place, we are advising passengers intending to fly from Shannon Airport to contact their airline before travelling to the airport.
"This is a precautionary measure and is in effect until the storm is expected to abate on Saturday evening.”
Update 5.21pm: A status orange wind alert is in place for Cork from 3am to 9am tomorrow morning.
High winds are epxected to continue until lunchtime, according to Cork City Council.
The Council are advising people to travel with care and said no tidal flooding is expected tomorrow.
The Council has also announced a number of road closures for today.
South Terrace and Rutland Street have re-opened.
Update 4.38pm: Cork City Council has announced a number of road closures due to the recent adverse weather.
South Terrace and Rutland Street will be closing at 5pm due to heavy rainfall and flooding.
"It is hoped they will be re-opened at 9pm," the Council said.
Dalys Bridge (Shakey Bridge) on the Mardyke has been closed today to facilitate a full engineering inspection. Closure effective until next Wednesday.
Centre Park Road (from the Marina to the Link Rd) is closed and will remain so even after completion of tree removal operations due to serious damage to road and footpath surfaces.
Centre Park Rd (from the Link Rd to Victoria Rd) is closed to pedestrians but will be opened today for vehicular traffic only.
The Marina (from Blackrock to the Centre Park Road Junction) is and will remain open as normal between Blackrock and the Marina/ Centre Park Rd Junction.
South Terrace and Rutland Street will be closing at 5 due to heavy rainfall and flooding, it is hoped they will be re-opened at 9.— Cork City Council (@corkcitycouncil) October 20, 2017
Update 3.24pm: Clare County Council has urged the public to avoid exposed coastal locations.
Meanwhile, An Garda Síochána has issued an advisory to those travelling to matches on Sunday in Paírc Uí Chaoimh, Cork.
The 202 bus from the city centre will provide pedestrians access to the grounds.
Cork: Due to impending storm “Brian” and the current issues with flooding on the roads, damage to footpaths and trees around Pairc Ui Chaoimh patrons are being advised to arrive early for the matches on Sunday, park in the city or the Boreenmanna Road.1/2— An Garda Síochána (@GardaTraffic) October 20, 2017
Cork 2/2 Pedestrians are advised to walk to the grounds via Monahan’s Road (as Centre Park Road is currently closed to pedestrians) or via Maryville.
The 202 Bus from the City Centre will provide pedestrians access via Maryville to the grounds.— An Garda Síochána (@GardaTraffic) October 20, 2017
Update 1.45pm: Cork county Council has warned that tidal surges this evening may cause flooding in Bantry, Clonakilty, Youghal and Midleton between 5pm and 7pm this evening.
Weather Warning for Cork - Wind & Rain - Tidal surge may cause flooding in for Bantry, Clonakilty, Youghal & Midleton - sand bags available pic.twitter.com/P2xYo21OgT— Cork County Council (@Corkcoco) October 20, 2017
There are also concerns in the mid west and midlands region where it is feared increased localised flooding may occur because of high tides and debris in rivers.
Cork City also remains on alert with fears that high tides this evening may cause flooding in certain areas after 5pm.
Update 1.27pm: Met Éireann issues two new Weather Warnings
National forecaster Met Éireann has today issued two new Weather Warnings as Ireland prepares for the incoming Storm Brian.
A Status Orange Wind Warning has been issued for the coasts of Mayo, Galway, Clare, Kerry, Cork, Waterford and Wexford.
“Southeast winds of mean speeds 55 to 65km/h with gusts of 90 to 110km/h, will veer west or northwest and strengthen further during the night, reaching orange level with mean speeds of 65-80 km/h with gusts 110-130 km/h,” the warning states.
“Winds will ease to yellow warning level during Saturday evening.”
The warning is valid from 10pm tonight until 10pm on Saturday night.
A Status Yellow Wind Warning will take effect in the same time period. This applies to counties Cavan, Monaghan, Donegal, Dublin, Carlow, Kildare, Kilkenny, Laois, Longford, Louth, Wicklow, Offaly, Westmeath, Meath, Leitrim, Roscommon, Sligo, Limerick and Tipperary.
“South or southeast winds, later becoming northwest will reach mean speeds of 55 to 65 km/h with gusts up to 110 km/h,” it states.
“The strong winds will occur in various parts of the country during different time periods, with winds in northern areas probably not peaking until Saturday afternoon.”
The rain has started bucketing down in Kerry, expect floods this evening if it keeps up like this #StormBrian— Jackie Healy-Rae (@Jackie_HealyRae) October 20, 2017
A Status Yellow Rainfall Warning for Donegal, Galway, Leitrim, Mayo, Sligo, Clare, Cork, Kerry, Limerick and Waterford has been in effect from 9am this morning and will continue until 9pm.
Met Éireann has warned that affected counties could see up to 50mm of rain over the period.
Aimsir an lae inniu: pic.twitter.com/J8RJxes1q3— An Aimsir Láithreach (@AimsirTG4) October 20, 2017
Update 10.21am: Cork City council advise motorists to exercise caution
With heavy rainfall expected throughout the afternoon Cork City Council has advised motorists to exercise caution with a minor risk of flooding in the Morrisons Island, South Terrace and Wandesford Quay areas of the city from 5.30pm-7.30pm due to high tides.
The council has said the situation will continue to be monitored but said they believe main impact of any tidal flooding will only be on traffic.
Met Éireann have also warned that the heavy rain this afternoon could also cause localised flooding elsewhere.
Yesterday's heavy rain lead to localised flooding throughout the country as here at Glanmire and Knockraha in county Cork.
Earlier: Ireland braces for Storm Brian with yellow and orange warnings in place today and tomorrow
A Status Yellow Rainfall warning affecting all Atlantic coastal counties from Donegal to Waterford comes into effect from 9am as the country's braces itself for Storm Brian.
The worst of the storm is due to reach our shores early tomorrow morning, when a Status Orange Wind Warning will be in place for western and southern coastal counties.
Winds are forecast to gust up to 130 kilometres per hour, with a risk of flooding along coasts.
The second named storm of the season, caused by a "weather bomb" of low pressure in the Atlantic Ocean, Storm Brian's arrival comes as 50,000 customers remain without power due to Storm Ophelia.
Brittany Ferries sailings on the Roscoff / Cork route today and tomorrow have been cancelled because of the weather.
The company apologises for the inconvenience and is currently contacting all passengers scheduled to travel, to offer assistance.
Passengers can also contact the Brittany Ferries call centre at 021 4277801 during office hours.
Climate Action Minister Denis Naughten said that southern counties are worst affected.
"The ESB staff in other parts of the country, when they get their own customers connected, are also being deployed to the other parts of the country, to Cork, to Waterford, to Wexford, to try and get people back as quickly as possible,
"The unknown in relation to this is the new storm that's coming in."
Yesterday, UK Met Office Spokesman Grahame Madge said "dramatic waves" could also pose a threat to life as Storm Brian moves in on Saturday, and warned against anyone tempted to pose for "storm selfies" along the coast.