Updated

Crowds thinned Tuesday on the beaches of North Carolina's Outer Banks ahead of a tropical weather system that threatened to bring strong winds and heavy rains that could flood low-lying areas.

Elsewhere, a powerful hurricane threatened to pass "dangerously close" to Hawaii, and a hurricane watch was issued for parts of Florida's Gulf Coast because of a tropical depression in the Gulf of Mexico.

On North Carolina's Hatteras Island, a slow stream of dozens of cars from places including Maryland, New York and Ohio headed north toward a bridge to the mainland — but other vacationers stayed and some surfers dove in for taller waves. Several Outer Banks businesses reported cancellations and slower foot traffic.

Some beaches were all but empty. Near Rodanthe, a couple and their 11-year-old son had the shore to themselves for a morning stroll. Joe and Kelley Walker of Markham, Virginia, said their family plans to wait out the rain with movies or card games.

"We're not worried about the storm so much unless they say there's something to worry about," Joe Walker said.

In nearby Frisco, whipped-up waves attracted out-of-town surfers. A break in the rain before more showers were expected also brought families out at midday.

Steven Kavika, a 58-year-old surf instructor, said he relished the opportunity.

"I saw it coming in last week and kind of made a prediction of what day would be best to come down," said Kavika, who drove down with a friend from Virginia Beach, Virginia.

The weather system was expected to pass near the Outer Banks by late Tuesday before eventually curving out to sea, likely reaching tropical storm status overnight with sustained winds of 45 mph, according to the National Hurricane Center.

Heavy rains of up to 5 inches were expected in some areas.

With the storm centered about 60 miles (95 kilometers) south of Cape Hatteras as of 5 p.m., a tropical storm warning was in effect for much of the Outer Banks. Forecasters have said it's not expected to surpass tropical-storm strength.

Coastal Carteret County emergency officials issued an advisory on Tuesday saying that wind problems were likely to be "mostly minor," but advised residents in case trees topple or lightweight objects are blown around.

At the same time, a tropical depression in the Gulf of Mexico prompted the National Hurricane Center to issue a hurricane watch for areas of Florida's Gulf coast stretching from the Anclote River northwest of Tampa to Indian Pass on the Panhandle. An area west of Indian Pass was under a tropical storm watch.

Forecasters say they expect that system to turn to the northeast toward Florida and become a tropical storm by sometime Wednesday. That depression was about 345 miles west of Key West, Florida.

National Weather Service meteorologist Tom Lonka said the center of the storm approaching North Carolina should stay offshore, but the Outer Banks will be lashed with rain and wind through Wednesday.

"There'll be rain showers coming on shore, rain bands and gusty winds," he said by phone Tuesday.

Lonka also said the storm in the Gulf was forecast to move across northern Florida later this week toward the Atlantic, but likely to stay south of North Carolina. Still, he cautioned its path was difficult to predict days in advance.

At Ride The Wind Surf Shop on Ocracoke Island, owner Bob Chestnut said he canceled all of his kayak tours and other rentals for Tuesday because he was concerned about the wind. Foot traffic was sparse.

"The amount of day-trippers has been pretty minimal because I think people were worried they'd get down here and not be able to get back," he said by phone, referring to people who take a ferry to the island on the southern stretch of the Outer Banks.

Byron Miller, manager of The Ocracoke Harbor Inn, said one person cancelled because of the forecast, and business is a little slower than usual.

Thousands of miles away, residents of Hawaii's Big Island are bracing for what could be the first Pacific hurricane to make landfall in that state in decades.

Meteorologist Chevy Chevalier said Tuesday that Pacific hurricane Madeline, now a major Category 3 storm, is expected to weaken but likely will remain a hurricane as it passes Hawaii. The forecaster said any shift in the storm's forecast track could mean it would hit land.

Chevalier says the last hurricane to make landfall in Hawaii was Hurricane Iniki in 1992, which hit Kauai Island.

A second Pacific hurricane called Lester is still far from Hawaii.