The advisory, which is in effect from 2 a.m. until 10 a.m. Wednesday, includes Northern Westchester, Putnam and Rockland.
The entire region will see overnight temperatures dipping to the mid- to low-30s
A frost advisory means widespread frost is expected and sensitive outdoor plants may be killed if left uncovered.
After areas of frost through 10 a.m. Wednesday in some spots in the Hudson Valley, temperatures will climb to around 50 degrees under cloudy skies.
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