Harrisburg, Pennsylvania – Temperatures will drop into the mid-30s overnight, creating a narrow window for frost formation that could damage plants before sunrise Sunday across central Pennsylvania.
According to the National Weather Service in State College, a Frost Advisory is in effect from 2 a.m. to 8 a.m. Sunday, with lows expected to reach around 34°F across a wide portion of the Susquehanna Valley and surrounding areas.
Impacted areas include Dauphin, Lancaster, Lebanon, Perry, Juniata, Mifflin, Snyder, Union, Montour, and Northumberland counties, with cities such as Harrisburg, Lancaster, Hershey, Selinsgrove, and Lewistown all within the advisory zone.
The coldest temperatures are expected in valley locations and sheltered rural areas, where near-ground freezing conditions can develop quickly under clear skies and light winds. These microclimates may briefly dip close to or below freezing, increasing the risk to sensitive vegetation.
Garden plants, early blooms, and unprotected crops face the greatest threat. Residents are urged to cover or bring in tender plants before 2 a.m., especially in low-lying areas where frost can settle more easily.
Conditions will improve after 8 a.m. Sunday as temperatures rise with daylight. However, additional chilly nights remain possible this spring, and further advisories could be issued if similar setups develop.
