PHILADELPHIA, Pa. – A frosty night is setting up across southeastern Pennsylvania, southern New Jersey, and northern Delaware as clear skies and calm winds drive temperatures near freezing by dawn Friday. The National Weather Service in Mount Holly has issued a Frost Advisory for southern counties where the growing season remains active, urging residents to protect tender vegetation.
According to the NWS, lows will dip into the low to mid-30s overnight for much of the Delaware Valley, with readings closer to the upper 20s in the Lehigh Valley and Poconos. Friday morning frost could briefly impact early commuters and gardeners before a quick warmup returns for the weekend. Afternoon highs will rebound into the mid-60s Saturday and Sunday under mostly sunny skies.
Forecasters say a strong cold front will push through late Sunday into early Monday, delivering the first true Arctic chill of the fall season. Temperatures will drop sharply into the 40s Monday, and morning lows could fall into the 20s across the interior by Tuesday. Despite the cold start to the week, no major precipitation is expected, and a return to seasonable 50s is likely by midweek.
Residents are advised to disconnect outdoor hoses, cover plants, and allow extra time for defrosting vehicles Friday morning. Boaters should note a Small Craft Advisory for coastal waters and a Gale Warning farther offshore.
Five-Day Forecast for Philadelphia, PA:
Fri: 62/37 – Cold early; sunny and crisp afternoon.
Sat: 65/49 – Mild; light breeze and sunshine.
Sun: 69/42 – Breezy; evening cold front arrival.
Mon: 49/32 – Much colder; brisk winds, clear skies.
Tue: 47/34 – Cold morning; gradual rebound late.
