But the U.S. National Hurricane Center says tropical storm-force winds are possible throughout the Azores beginning late Saturday.
Ophelia is the record 10th consecutive storm in the Atlantic this season to reach hurricane intensity, following on from the devastation of Harvey, Irma, Jose, Katia and Maria in the Caribbean and Gulf of Mexico.
"Met Eireann will maintain a close watch on the evolution and issue further advisories and warnings as these are warranted".
The storm was about 610 miles southwest of the Azores early Friday, packing maximum sustained winds of 105 mph.
Ophelia had winds of 90 miles per hour and could maintain that strength for the next day or two, the hurricane center said. The storm's center is forecast to continue moving east-northeast, passing near or to the southeast of the southeastern Azores Saturday and Saturday night, with only slight weakening expected over the next two days.
The storm, which is now a Category 2, was initially not thought to be a land threat, swirling far from the American and European coastlines in the middle of the Atlantic.
The current forecast says there is an nearly zero per cent chance of a storm forming in the next 48 hours, and a 20 per chance of formation within the next five days.
A stronger Hurricane Ophelia continued tracking northeastward on Thursday morning, far from the U.S.
The hurricane's maximum sustained winds early Thursday were near 85 miles per hour (140 kph) with some slight strengthening possible over the next day or two.