Long Island experienced showers and thunderstorms Thursday evening with more expected in the overnight hours, some with heavy rain, the National Weather Service said.
A line of storms came through around 8 p.m. in some places. But the most likely time frame for other systems to arrive is from midnight until Friday morning, especially for the Twin Forks, said Joe Pollina, a meteorologist based in Upton.
In all, the service had forecast from around half-an-inch of rain in eastern Suffolk to more than three-quarters of an inch in western Suffolk and Nassau County.
A flood advisory had been in effect for Nassau County through 2:45 p.m. Thursday as an earlier storm passed through, because of possible minor flooding in poor drainage areas, the National Weather Service said.
As of early evening, New York airports experienced delays of more than three hours but those were reduced to 15 minutes later Thursday night, according to the Federal Aviation Administration website.
The chance of rain late Thursday and into Friday morning ranged from 60 to 90 percent, the weather service said.
Once the system moves east into the Atlantic, the service forecasts a clear, mostly sunny weekend, with daily highs Friday near 77, and near 70 and 71 for Saturday and Sunday.