Irish weather authority Met Eireann has said it expects wet and windy weather from Storm Helene to hit the southern coast of the Republic on Tuesday, but does not expect any "severe or damaging weather".
The storm remained a Category 2 hurricane with maximum sustained winds of 100 miles per hour. Gradual weakening is forecast during the next few days.
The remnants of the storm could even end up bringing some drier conditions to the south west of the UK. On Thursday morning, South 17th Street, usually teeming with commuter traffic by 6:30 a.m., was almost devoid of cars.
All of the islands under watch were significantly impacted by Hurricanes Maria or Irma last September, with some of them still trying to rebuild. Tropical storms generate winds between 39 and 73 miles per hour, just below hurricane force. "Near the coast, the surge will be accompanied by large and destructive waves", the NHC added.
Isaac a little weaker and continues to lose organisation as it moves westward.
The powerful Atlantic storm is resting behind Hurricane Florence which is set to smash into the United States coast.
Helene is one of three major storms now swirling in the Atlantic.
Hurricane Warnings are in effect from the South Santee River in SC to Duck, North Carolina.
Some flooding was forecast early in the day for parts of North Florida, but those forecasts were adjusted later to include high swells and minor coastal flooding at high tide.
Isaac became the fifth hurricane of the season late Sunday and was initially expected to strengthen, potentially becoming a Cat 2 storm with 100 miles per hour winds, as it crossed warm ocean waters.
A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. The hurricane center is giving the system a 50 percent chance of becoming a tropical depression or storm within the next five days.
With the ground already saturated from recent rain, another drenching from Florence combined with winds could easily lead to trees being uprooted and widespread power outages, he said.