PHILADELPHIA, Pa. – The coldest air of the season will spill across the Mid-Atlantic late tonight, triggering Freeze Warnings from Pennsylvania through Maryland and New Jersey as temperatures tumble into the upper 20s to low 30s by dawn Friday. The National Weather Service warns this blast of Arctic air could end the growing season for many inland and elevated areas.
According to NWS State College, most of central and northern Pennsylvania — including the Susquehanna Valley, the Alleghenies, and the Poconos — will drop below freezing 11PM–9AM. Lows of 25–30°F are expected across Harrisburg, Altoona, Williamsport, and State College, with valleys likely even colder.
NWS Mount Holly has issued a Freeze Warning for northwest New Jersey and northeast Pennsylvania — including Sussex, Warren, Monroe, Carbon, and Northampton Counties — for the same period. These areas may see hard freeze conditions with widespread frost and subfreezing air before sunrise.
Farther south, NWS Baltimore/Washington placed western Maryland, the Shenandoah Valley, and the West Virginia highlands under a Freeze Warning from 2AM–9AM Friday, with lows near 29–31°F expected. The immediate Baltimore and Washington metro areas will remain just above freezing, though patchy frost is possible in outer suburbs.
Residents should protect plants, gardens, and outdoor plumbing ahead of the cold. Bring potted plants indoors, cover sensitive vegetation, disconnect hoses, and insulate outdoor faucets. Early commuters should expect frosted windshields and icy spots on bridges and shaded roadways.
Sunny skies return Friday, but it will stay cool, with highs only in the upper 40s to low 50s. A gradual warm-up is expected this weekend.
