Rime ice is formed when cooled water droplets in the air form into crystals on surfaces. Conditions of fog and temperatures in the low 30"s are perfect for its formation. The photo was taken in early December 2018 in Southern Minnesota.
<a href="//commons.wikimedia.org/w/index.php?title=User:Tamarajo&amp;action=edit&amp;redlink=1" class="new" title="User:Tamarajo (page does not exist)">Tamarajo</a>
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<span class="int-own-work" lang="en">Own work</span>