The National Climatic Data Center (NCDC) collects data on when first
and last frosts/freezes occur across the United States and probability
ranges. When data on this site indicate a greater likelihood of
freeze than the USDA cold hardiness map, gardeners would be well
advised to develop a strategy for protecting their frost-sensitive
plants. These maps are a good starting point, but do not provide you
with everything you may need to know to react. This site is supported
by NOAA (National Oceanographic and Atmospheric Administration. (***)
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