HURRICANE Ophelia will be the most severe weather event to his this country since Hurricane Debbie hit in 1961 - resulting in 15 deaths - Met Eireann has warned.
This evening Met Eireann confirmed that a red weather warning has been extended nationwide.
Speaking on this evening's weather forecast, meteorologist Joanna Donnelly told viewers "this is not the remnants of a hurricane - this is a hurricane".
Every school and college in the country will remain closed tomorrow as a result, the Department of Education has said.
The public have been urged not to make unnecessary journeys.
Employers have also been urged to give their employees guidance how working arrangements have been affected in light of the national red warning.
The issue of red level severe weather warnings implies that recipients take action to protect themselves and/or their properties; this could be by moving their families out of the danger zone temporarily; by staying indoors; or by other specific actions aimed at mitigating the effects of the weather conditions. It is the highest level of alert Met Eireann can issue.
Aer Lingus has said that over 50 flights have been cancelled so far. Affected passengers have been contacted by text.
The army remains on standby to offer assistance in the event there is severe flooding or storm damage in affected communities.
Gardai have advised cyclists in all counties to use public transport or drive rather than cycle in the conditions.
Nearly all court sittings nationwide have also been cancelled.
This affects all Supreme Court, Court of Appeal, High, Special, Circuit and District Courts sittings in the country.
Some Custody hearings of the District Court will go ahead via local arrangements, however it is hoped many of these can be conducted by video link.
People summonsed for jury duty for the first time or acting as a juror in an on-going trial should not report to courthouses Monday October 16th - but should instead report on Tuesday.
Officials have been holding a briefing at the National Emergency Coordination Centre today, with people being warned to stay indoors when the hurricane hits their area tomorrow.
The south, south west and west are set to be most-exposed to Hurricane Ophelia, including Waterford, Cork, Kerry, Galway and Mayo.
Met Eireann forecaster Evelyn Cusack told the briefing the weather event was almost unprecedented for this country.
The hurricane will hit the south west coast from around 6am tomorrow and will pass north east across the country.
It had been described as “rapid moving” and will have passed by Tuesday.
Sean Hogan, national director for fire and emergency management, said it was an “extreme weather event.”
“The comparable weather event we are looking at is Hurricane Debbie in 1961,” he said.
“Everyone in the country needs to take heed of what’s coming,” he said.
Met Éireann has also warned that structural damage and flooding is possible.
"The swathe of the area affected by the storm may exceed 100km," Mr Hogan explained.
Ms Cusack said Met Eireann took the "unprecedented step" of issuing a status red warning more than 48 hours before a weather event.
"We issue very few red alert warnings and certainly, they are always within a 24-hour period," she explained.
She referred to weather charts showing the hurricane's predicted pass over Ireland, which she said looked "a little alarming".
"That's because it is an unprecedented weather situation," she said.
She described the fine weather of the weekend as "the calm before the storm."
She said only 15 hurricanes have passed within 200 nautical miles of the Azores since scientific monitoring began in 1851.
Farmers have been warned to ensure that any equipment they have is secured.
Soldiers have been mobilised in areas of the country including Kilkenny to help fill sandbags, while Defence Forces engineering assets such as pumps have also been stood up.
People have been warned to stay away from coastal areas tomorrow as the storm passes and also to avoid fallen cables.
"Following a special meeting of the Government Task Force on Emergency Planning in response to the imminent Storm Ophelia, the Department of Education and Skills is now informing all schools in areas affected by Met Éireann’s status red wind alert that they are to act on the Department’s advice and remain closed tomorrow, Monday 16 October," the Dept said in a statement."
"For parents, this means that their children will not attend school tomorrow in any area where there is a status red wind alert already announced or announced in the intervening time.
Earlier, Minister for Foreign Affairs, Simon Coveney urged the public to take the severe weather warnings seriously.
The former Defence Minister wrote on Twitter: “Anybody not taking storm Orphelia seriously should think again - I don't remember ever seeing a forecast for the south coast quite like this.”
Met Eireann’s Gavin Gallagher said: “As you can imagine this morning, there’s quite a lot going on. “It’s quite unusual to have such a strong storm system in this part of the world. It’s the strongest hurricane in the Atlantic on record in history.”
“(Met Eireann forecasters) just had a four-way conference call with the National Hurricane Centre in Miami, the National Weather Service in the US and the Met Office in the UK.”
Mr Gallagher stressed that the hurricane will downgrade to a storm by the time it hits Ireland.
"It has the potential to be as bad as Debbie," said Pat Clarke of Met Eireann. "The track is pretty much consistent now. These things can take on a life of their own but it certainly has the potential to be similar [to Debbie]."
At this stage, there is strong evidence from weather forecast models that the remnants of Ophelia will track close to or over parts of Ireland, but at present, there are still a wide range of possible outcomes.
Met Eireann forecasters will be tracking Ophelia's evolution in the next 24 hours, with emergency response teams still hopeful the country will escape the worst of the storm.
The US National Hurricane Center said yesterday Ophelia had become a "rare category 3 hurricane south of the Azores", making it the "sixth major hurricane of the 2017 season".
"No significant change in strength is expected today, but gradual weakening should begin tonight or Sunday. However, Ophelia is still expected to remain a powerful cyclone with hurricane force winds for the next couple of days as it approaches Ireland," it said.
The issue of red level severe weather warnings is a comparatively rare event and implies that people take action to protect themselves and/or their properties.
This could be by moving their families out of the danger zone temporarily, staying indoors, or by other specific actions aimed at mitigating the effects of the weather conditions.
The Office of Emergency Planning in the Department of Defence has taken a lead role in co-ordinating a response across State responders.
Ophelia is expected to pass Ireland tomorrow, with forecasters warning of severe disruption, coastal flooding and structural damage to buildings. People have also been warned of the risks posed by falling trees with transport infrastructure likely to be hit along the western seaboard.
Environment Minister Denis Naughten yesterday warned that the country should prepare for more "very severe" storms which will "ravage through people's homes".
"You are going to see an increased frequency of extreme weather conditions like the 100-year floods happening every five or six years," Mr Naughten told the Sunday Independent.
"The climate change scientist won't relate any one particular event to climate change but the reality is we have seen in Ireland over the last decade very unusual weather incidents that would have been spread out over a much larger period up until now," he said.
The Department of Education advises that schools "should consider not opening where a Status Red weather warning related to wind is forecast to coincide with the period/s during which students and staff would be expected to be travelling to and from school.
"Whether the school should open later in the day where an improvement to the weather is forecast is a decision which should be taken in consultation with An Garda Siochana, the local authorities, school transport services and other appropriate agencies based in the school's area."
Age Action Ireland have urged people to do their best to ensure elderly relatives stay safe during the worst of the storm.
Justin Moran, Head of Advocacy and Communications with Age Action, said: “Some of the reports are predicting the worst storm to hit Ireland in 50 years so we would urge older people, particularly those living in alone in isolated areas, to take every precaution.
“They might like to consider staying with a relative for the next couple of days. They should certainly ensure they have enough food and fuel to be comfortable in case the roads become dangerous.
“We would also urge the neighbours of older people to please make the effort to look in on them to make sure they’re okay if your community is particularly hard hit by the storm.
“Even if they’re alright many older people get an enormous sense of comfort from knowing someone is keeping an eye out for them.”
EMERGENCY measures will be taken in the next 48 hours as the country braces itself for a ferocious storm comparable with Hurricane Debbie, the most powerful cyclone ever to hit Ireland.