Rain rates near two inches per hour could be possible with stronger storms, and some of the storms may lead to flash flooding.
The highest risk for rain is Saturday evening into Sunday morning, the NWS said.
Most of the region will likely stay dry during the day until rain moves in later.
Parts of Southern NJ by the Delaware River are under a slight risk for excessive rainfall leading to flash flooding, forecasters said.
Before rain moves in over the weekend, Friday is expected to be mainly dry throughout the Garden State, though there is a risk for scattered showers before noon in South Jersey.
Here's the latest weekend forecast from the NWS:
NORTH JERSEY
Friday: Mostly sunny, with a high near 81. Northwest wind 9-11 mph.
Friday Night: Mostly clear, with a low around 61. Northwest wind 5-7 MPH becoming light and variable.
Saturday: Mostly sunny, with a high near 79. Northeast wind 5-7 MPH becoming southeast in the afternoon.
Saturday Night: A chance of showers, then showers and possibly a thunderstorm after 11 p.m. Low around 67. Southeast wind 6-8 MPH. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Sunday: Showers and possibly a thunderstorm before 8 a.m., then a chance of showers and thunderstorms between 8 a.m. and 2 p.m. High near 82. South wind 5-9 MPH becoming northwest in the afternoon. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Sunday Night: Partly cloudy, with a low around 68.
CENTRAL JERSEY
Friday: Mostly cloudy, then gradually becoming sunny, with a high near 82. Northwest wind around 5 MPH.
Friday Night: Mostly clear, with a low around 60. South wind around 5 MPH becoming calm.
Saturday: Increasing clouds, with a high near 81. Southeast wind 5-10 MPH.
Saturday Night: A chance of showers and thunderstorms before 2 a.m., then showers and possibly a thunderstorm between 2 a.m. and 5 a.m., then showers after 5 a.m. Low around 67. Southeast wind around 5 MPH. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Sunday: Showers before 11 a.m., then showers likely and possibly a thunderstorm between 11 a.m. and 2 p.m. High near 84. Calm wind becoming southwest around 5 MPH. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Sunday Night: Partly cloudy, with a low around 67.
SOUTH JERSEY
Friday: Scattered showers, mainly before noon. Mostly cloudy, with a high near 80. East wind around 10 MPH. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.
Friday Night: Mostly cloudy, with a low around 68. East wind around 5 MPH.
Saturday: Mostly cloudy, with a high near 81. Southeast wind 10-15 MPH.
Saturday Night: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2 a.m. Low around 71. Southeast wind 5-15 MPH. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Sunday: Showers and possibly a thunderstorm, mainly before 2 p.m., then a slight chance of showers and thunderstorms after 2 p.m. High near 84. West wind 5 to 10 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.