A Flood Watch is in effect for the entire Jersey Shore region through Sunday night.
The National Weather Service says period of rain, heavy at times, will occur during the day.
At 7:45 a.m., heavy rain is moving through the Philadelphia area and the central portion of the Jersey Shore, with more on the way.
Forecasters say the heaviest rain will shift slowly northward throughout the day toward more of New Jersey.
The National Weather Service warns of likely low-lying flooding where the heaviest rain occurs.
Rainfall amounts may also result in flooding on area streams, creeks, and rivers later in the day.
Precipitation will end by Monday morning, and skies will clear throughout the day.