The Met Office has issued severe weather alerts, warning of potential power cuts, flying debris and disruption to transport and mobile phone signal.
The tropical storm has been making its way across the Atlantic and Ophelia's remnants are set to reach home shores on Monday, resulting in "exceptional" weather.
Yorkshire is among the areas covered by weather warnings.
Northern Ireland is covered with an amber warning - meaning there is a "potential risk to life and property", issued when forecasters believe people need to be prepared to change their plans and "protect you, your family and community from the impacts of the severe weather based on the forecast".
Very windy weather is expected across the entire region, while a yellow warning is in place for much of Wales, Scotland, parts of Yorkshire, north east England, north west England, south west England and the West Midlands.
Gusts of 55-65mph are likely across Northern Ireland with 70-80mph gusts in the far south-east.
A smaller area of very gusty winds is then likely to run across Northern Ireland from the west with 65-75mph gusts possible for a short period of time in any one location.
Longer journey times and cancellations are likely, as road, rail, air and ferry services may be affected as well as some bridge closures.
Heavy rain is also possible in parts of Northern Ireland and western Scotland.
Met Eireann have issued a "status red" weather alert for Galway, Mayo, Clare, Cork and Kerry, warning of severe winds and stormy conditions.
Met Office forecaster Luke Miall said: "We do get these sorts of strengths of winds most winters. We generally get a few storms that will see these sorts of winds, but this is quite a substantial system because of where it's coming from as well.
"And to get that sort of south-easterly strength across the south east of Northern Ireland - you don't generally get that.
"You tend to get strong south-westerly winds because the systems come up across the northern half of the UK.
"So yeah I'd say it's pretty exceptional."
Mr Miall said Ophelia will have gone through a transition on its way across the Atlantic and will no longer be a hurricane, but will still bring "hurricane-force" winds.