Models differ on how Irma might impact North Carolina

On Sunday afternoon, the storm had sustained winds of about 115 mph and prompted hurricane watches for portions of the Leeward Islands.

"This is definitely a strong hurricane as it continues to move to the west," said WRAL meteorologist Aimee Wilmoth. "We still really don't know the impact Irma might have on the United States, but this is definitely a storm that we're going to have to watch."

Wilmoth said both the American and European forecast models show that Irma will be over the southern portion of the Bahamas by Friday afternoon and will move into the northern Bahamas by next Sunday. The storm is expected to become a Category 4 storm by time it arrives.

"It does look like Irma will continue to strengthen over the coming days as it moves into more favorable conditions, including warmer water," Wilmoth said.

The storm will track toward the United States next Monday, but the models then differ on where it will go after that.

Wilmoth said the American model shows the storm moving in toward the South Carolina and North Carolina coasts while the European model keeps the storm entirely offshore.

"It's a pretty dramatic turn of events. If it stays offshore, things would be much better. If it comes on shore, it would be much worse," she said.

Wilmoth said it's too early to know for certain the direct impact Irma will have on the United States, but people should pay close attention to the forecast and prepare themselves.

"I would say that anyone around Florida to Virginia needs to pay very close attention to the forecast for Irma," she said.