The Met Office said Ophelia's gusts are forecast to make it Britain's strongest ex-tropical storm since September 2011's Hurricane Katia, which had 129km/h low-level gusts and caused one death and widespread travel chaos.
Winds of more than 129km/h would make the storm Britain's strongest ex-hurricane since Hurricane Lili's 148km/h gusts in 1996, said AccuWeather, the world's second biggest commercial forecaster.
Late last night, a Met Office spokesman told MailOnline that the storm should be hitting Ireland by late morning (local time).
Meanwhile, 30 years ago, weatherman Michael Fish famously told the UK that a hurricane "was not coming" just hours before the country was battered by 185km/h winds.
But the 73-year-old has now admitted that Hurricane Ophelia "looks nasty" and said the timing of the storm was a "terrible coincidence".
The gales today are set to batter the UK exactly 30 years after the Great Storm of 1987 which killed 22 people, destroyed around 15million trees and caused NZ$3.7b damage.
The whole of Ireland has been placed on a red alert as the storm continues to approach the country this morning.
It comes as swarms of deadly jellyfish have been seen washed up on beaches across the south coast after being blown ashore by the hurricane.
In Ireland, schools, government buildings and courts are due to close on Monday (local time), with the Met Office issuing severe weather alerts, warning of potential power cuts, and disruption to transport and mobile phone signal.
A yellow weather warning has been issued for much of the west of the UK with a more serious amber warning issued for Northern Ireland, which is expected to take the brunt of the storm.
The Met Office warned: "Some damage to buildings, such as tiles blown from roofs could happen, perhaps leading to injuries and danger to life from flying debris.'
A Met Office spokesman told MailOnline: "Hurricane Ophelia is slowly edging its way closer to us.
"The centre of the storm will hit south west Ireland first, at around 11am (local time). There has been a red warning issued for the whole of the Republic of Ireland - which is something I've never seen before and there are likely to be 128km/h winds there.
"Later in the day there will be 112lm/h winds hitting west Wales and the Isle of Man.
"There will be potential flooding in south west Scotland and there could be some coastal issues because of the storm."
On Tuesday the windy weather is expected to spread across to the North and southern Scotland with a yellow warning remaining in place for these areas. The wind is expected to ease to sub-warning levels by the evening.
Meanwhile in the Republic of Ireland weather forecasters are warning of a potential threat to life as a red weather warning - the highest of its kind - was issued in several western states, including Galway, Mayo, Clare, Cork and Kerry. The rest of the country is on amber alert.
In Dublin the National Emergency Co-ordination Group met this morning to discuss preparations for the arrival of the storm while school bus services have been cancelled to ensure child safety in the five western counties.
Irish Defence Forces are on standby to deploy resources, including transport and engineering assets.
The public has been advised to stay off the roads during the height of the storm if possible and to avoid coastal areas. Cyclists have also been warned not to go out on their bikes.
The National Directorate for Fire and Emergency Management said the storm is expected to hit Kerry at 6am (local time).
The storm front will track northwards on Monday night, leaving Irish coastal waters before midnight (local time).