Heavy rain is expected to begin falling in the northwestern part of the New Jersey, and parts of Pennsylvania between 3 and 5 p.m., the National Weather Service said.
The storm will begin elsewhere between 4 and 8 p.m.
Large hail, flash flooding, and wind gusts up to 60 mph are likely.
Western NJ is at an "enhanced" risk for strong storms while the eastern side is at a "slight" risk.
Click here to follow Daily Voice Northern Highlands and receive free news updates.