Some of the US coast may be under a tropical storm or hurricane watch later Sunday, the center said. Those on the Carolina and mid-Atlantic coasts are warned to monitor the storm's progress.
As of 11 a.m. Sunday the storm was roughly 475 miles south-southeast of Cape Hatteras, North Carolina.
"Regardless of the exact forecast track," the storm is so big that "tropical storm-force winds could reach a portion of the North Carolina coast by mid-week," the NHC said.
Maria weakened to a Category 2 storm Sunday, with sustained winds of about 105 mph. The NHC said it expected the storm to weaken further by Monday night or Tuesday.
Even so, Maria still packs a dangerous punch.
Swells generated by Maria are increasing along portions of the southeastern United States coast and Bermuda and will be increasing along the Mid-Atlantic coast later today," the center said Sunday, warning that such swells can cause "life-threatening surf and rip currents."