Hurricane Joaquin is seen churning in the Caribbean, Wednesday, Sept....

Hurricane Joaquin is seen churning in the Caribbean, Wednesday, Sept. 30, 2015. Joaquin was upgraded to a Category 1 hurricane early Wednesday. Credit: Getty Images

The East Coast probably will be spared a direct hit from Hurricane Joaquin, a Category 4 storm battering the central Bahamas, the National Hurricane Center said Thursday.

"We are becoming optimistic that the Carolinas and the mid-Atlantic states will avoid the direct effects from Joaquin," the hurricane center said.

However, the center could not rule out the hurricane directly affecting the East Coast.

Joaquin is expected to pass east of Long Island from Monday evening into Tuesday morning.

While the hurricane hovered over the eastern Bahamas Thursday, there were no immediate reports of injuries or deaths.

Once it leaves the Bahamas, forecasters think the hurricane will steadily weaken as it moves north.

At 8 p.m. Thursday, its winds were about 130 mph.

Some additional strengthening was possible Thursday night and Friday, with some fluctuations in wind intensity possible Friday night and Saturday.

"While Joaquin's path appears to be edged farther east . . . the range of possible error in a forecast four days away is considerable, so we have to continue to plan for the possibility of storm conditions here Monday," said Bill Korbel, News 12 Long Island meteorologist. "If the storm does pass out to sea, great. If not, we are prepared."

Even if the system gives Long Island a pass, the area could still see rainfall, winds, erosion and coastal flooding, forecasters said.

"Whether Joaquin directly impacts the East Coast or not, tropical moisture from Joaquin is expected to increase the potential for heavy rainfall," said the National Weather Service's Upton office.

A different weather system also is expected to dump rain on the Island -- well before Joaquin passes by.

Between Thursday night and 8 p.m. Sunday, the region is expecting around an inch of rain, mostly Friday and overnight from a frontal system forecast to move up the eastern seaboard ahead of the hurricane.

"Indications are that the frontal system may align itself farther east," said weather service meteorologist Jay Engle, "with heavy rainfall falling just offshore or on the immediate coast."

Much of the eastern United States has already received soaking rains from the frontal system during the past week.

Drenching rains caused major flooding in the Carolinas Thursday, drowning a woman whose car quickly filled up with water and prompting flash flood warnings from historic Charleston, South Carolina, to Washington, D.C. With Gary Dymski