The National Weather Service in Raleigh has issued a frost advisory through 9 a.m. Sunday for the Triad.
With temperatures expected to dip into the 30s overnight, weather forecasters say patchy frost can be expected into Sunday morning.
Along with Guilford and Forsyth, nearby Alamance, Davidson and Randolph counties are also under the advisory.
Frost could kill sensitive outdoor vegetation if left uncovered, the weather service said.
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