As Kirk continues to move over the Eastern Caribbean Sea, broad areas of heavy showers, thunderstorms and strong winds are gradually diminishing over the Windward Islands south of Dominica.
Kirk had maximum sustained winds of 50 miles per hour and was located about 140 miles west-southwest of St. Lucia.
The NHC has advised that reports from an Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds have decreased to near 45 miles per hour (75 km/h) with higher gusts.
Velda Joseph, in a statement, said that the organisation had been in contact with the St Lucia Meteorological Services and other relevant parties and that the tropical storm warning for the island had been lifted. A Flood watch will remain in effect until further notice.
Schools and workplaces were closed in Dominica and Guadeloupe.
Tropical Storm Kirk has moved into the Caribbean, but the associated inclement weather is still spreading across portions of the Lesser Antilles.
The storm is expected to soon weaken to a tropical depression and degenerate into a low pressure trough by late Saturday.
In Puerto Rico, which was hit by Hurricane Maria previous year and is still recovering from the storm, Kirk was expected to bring between 2 and 4 inches of rain to the eastern part of the island. St. Croix and eastern Puerto Rico could see 4 inches to 6 inches Friday and Saturday.
Forecasters say Hurricane Rosa has quickly turned into a Category 3 off Mexico's Pacific coast, but it's not expected to threaten land before next week.
St Lucia was returning to normal on Friday after Tropical Storm Kirk drenched the island with heavy rains and winds, causing electricity blackouts in some areas as a result of trees falling on power lines.