On Thursday at 1:57 a.m. the National Weather Service released a frost advisory valid for Friday between 2 a.m. and 9 a.m. for Franklin, Dauphin, Lebanon, Cumberland, Adams, York and Lancaster counties.

The weather service states to prepare for, "Temperatures in the 30s will result in frost formation."

"Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered," explains the weather service. "Those with agricultural interests should protect sensitive vegetation. Valley locations and sheltered rural areas will experience the coldest temperatures."

Frost advisory - this is what it means

Frost advisories are issued from May to October (but can be extended if necessary) when temperatures, winds, and sky cover are favorable for frost development

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