On Thursday at 1:54 p.m. an updated frost advisory was issued by the National Weather Service valid for Friday between 1 a.m. and 8 a.m. for Delaware and Philadelphia counties.

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

"Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered," describes the weather service. "Take steps now to protect tender plants from the cold."

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. This is most likely to happen when the temperature is 36 degrees or less. In some cases, the frost is severe enou

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