An approaching cold front means a chance of scattered showers and thunderstorms for most of Long Island through early Friday, the National Weather Service said.

The front, swooping in from the northwest, converges with a low-pressure system in the southwest and brings a 50 percent chance of rain starting Thursday afternoon and into Thursday night. By Friday, the chance of rain is 20 percent, the Upton-based service said.

The front will move south later in the morning Friday, giving way to clear skies and a sunny weekend, with highs in the 80s and nightly lows in the mid 60s.

New rainfall amounts predicted for Thursday likely will be less than a tenth of an inch, the forecast said. Some higher amounts could be possible during thunderstorms, however.

If there is heavier ran, it likely will be west of the Nassau-Suffolk border, the service said, with some parts of Nassau County expected to get up to three-tenths of an inch, the service said.

Meteorologist David Stark of the service said the North Shore of Suffolk was hit with a stretch of thunderstorms for about an hour beginning about 10:30 a.m. Thursday.

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Stark said a string of storms reached from Stony Brook to Wading River on the North Shore, delivering up to an inch of rain in some spots. There were some reports of surface flooding, he said.

"Radar estimates showed rainfall of 1 to 2 inches in an hour, so it was not out of the question for some folks to pick up an inch of rain," Stark said.

He also said there were reports of lightning strikes and heavy winds, but no damage to property.

There also were some reports of isolated showers on the South Shore, near Fire Island at sunrise, he said.

After Friday morning, the weekend forecast looks "near perfect," Stark said.

"We'll be warm in spots early Friday but then the humidity becomes much lower, so the weekend should be nice," he said.