Industrial snow , which is caused by emissions, especially from water vapor and condensation kernels from industrial plants.
Industrial snow requires three ingredients: humidity, cold and dust particles. This does not happen very often, so industrial snow is rare. Humid and cold air is usually provided by fog. Industrial snow often forms at night when the fog cools even more. Industrial systems provide the necessary dust particles.
This week's #Photo52 Challenge theme is Wintermas! , Challenge, week number 51 by 
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