Helene strengthened to a hurricane Wednesday, as it churns its way toward the U.S.

Forecasters anticipate the storm will make landfall as a major hurricane — at least a category 3 — Thursday along the Big Bend or Panhandle area of Florida.

Helene is expected to become a massive hurricane, potentially growing into a Category 4 storm. Forecasters are warning that it could have a wind swath more than 400 miles wide.

Follow live updates on Hurricane Helene

Florida, Georgia, North Carolina and South Carolina have declared emergencies ahead of the storm.

Officials are urging residents to take precautions ahead of Helene's landfall, and evacuations have been ordered in places along Florida’s west and northwestern coasts.

Potential flooding is a concern in North Carolina, Georgia and South Carolina.

The system became a tropical storm Tuesday in the western Caribbean Sea and caused flooding in the Cayman Islands.