The National Weather Service in Mount Holly, NJ, reports a chilly forecast for the Mid-Atlantic region as high pressure settles in. Tonight will see clear skies and light winds, leading to very efficient radiational cooling. Many areas can expect their first freeze of the season, with temperatures dropping into the upper 20s to low 30s. Urban areas like Philadelphia may stay slightly warmer, around the mid to upper 30s, while coastal regions will experience mild temperatures due to warmer water influences.
As the week progresses, the high pressure system will move offshore, bringing a light southerly flow and a warm-up. Monday will be dry and mainly sunny, with temperatures reaching the low to mid 60s. Conditions are expected to remain tranquil through mid-week, with mostly clear skies and temperatures gradually warming into the upper 60s and low 70s by Tuesday. Nighttime lows will range from the 30s to 50s.