A low pressure system will bring light rain showers across the region on Monday afternoon and into the evening hours, then move out to sea.
An isolated thunderstorm is possible in some areas, and wind gusts of 25-30 mph at times through Monday night.
Then it gets unseasonably cold later Monday night as a high pressure system builds across the area Tuesday and Wednesday, drawing cold air down from the Great Lakes, according to the National Weather Service.
A freeze warning is active from 1 to 10 a.m. Tuesday, with a freeze watch from Tuesday night into Wednesday morning for southeastern Pennsylvania, South Jersey and Delaware, where the growing season has begun
Dry weather is forecast for Tuesday and Wednesday, but night-time temperatures through the weekend will be around or below the freezing mark, except for a brief warmup Wednesday and Thursday nights, forecasters said.
Showers arrive Thursday night into Friday, and temperatures should be low enough in the northern section of the region for rain to turn to snow showers for a while from late Thursday into Friday morning.
Next weekend looks to get cold again.
In New England, forecasters say more of the area than previously thought could see up to 6 inches of snow from an April storm.
The weather service said Monday afternoon that the areas in the maximum range for snowfall have expanded east into Boston and the suburbs and north into southern New Hampshire.
Central and western Massachusetts as well as northern Rhode Island and northern Connecticut are also in the maximum range. Coastal areas were expecting less snow.
The slow-moving storm was expected to last through the evening, when temperatures were going to plummet.
Here's the 7-day forecast for the Philadelphia region from the weather service:
This Afternoon
Rain, mainly after 2pm. High near 62. West wind 13 to 15 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Tonight
Rain, mainly before 8pm. Low around 30. North wind around 17 mph, with gusts as high as 30 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.
Tuesday
Sunny, with a high near 44. North wind 13 to 15 mph.
Tuesday Night
Mostly clear, with a low around 28. North wind 5 to 9 mph becoming light and variable after midnight.
Wednesday
Mostly sunny, with a high near 54. Light southeast wind becoming south 11 to 16 mph in the morning.
Wednesday Night
A chance of showers, mainly after 11pm. Mostly cloudy, with a low around 46. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.
Thursday
Showers likely. Cloudy, with a high near 62. Chance of precipitation is 70%.
Thursday Night
A chance of showers. Mostly cloudy, with a low around 40. Chance of precipitation is 40%.
Friday
Mostly cloudy, with a high near 52.
Friday Night
Mostly cloudy, with a low around 32.
Saturday
Mostly sunny, with a high near 48.
Saturday Night
Partly cloudy, with a low around 32.
Sunday
Mostly sunny, with a high near 55.