Keep those umbrellas handy.
A front coming through after 8 tonight could start a string of at least five days with a threat to be wet, according to the National Weather Service.
The call for rainfall is strongest Tuesday and Wednesday, when some areas from northeastern Maryland to Trenton could get 1 to 3 inches, according to the National Weather Service.
Muggy weather Thursday through Sunday - highs could return to the mid 90s after a couple of days in the 80s - means a chance of showers or thunderstorms every day.
"We will need to keep an eye on the possibility of more intense storms, because with the hot/humid air, it will be very unstable and it will not take much to spark off some storms," according to a late morning forecast discussion.
Saturday is the only day with a less than 30 percent chance of precipitation.
Rain is also possible Monday through Wednesday of next week as well, according to the 10-day forecast at Weather.com.
Some rain is clearly needed, with less than 1.5 inches falling in the last 30 days - while heat waves were setting or tying records.
If the forecast lives up to its billing, the rainfall total for the last month could double or triple by Wednesday night.
For more on the forecast, go to http://go.philly.com/weather.