FOX19 - For the second time in a couple of weeks, northern Kentucky experienced "Power plant" snow.
Friday morning, some lake effect snow bands (circled below in purple) moved through after setting up off of Lake Michigan, and those were enhanced by the Miami Fort Power plant. (circled in blue.)
Areas of Union, Kentucky were the recipients of upwards of an inch or so of un-forecasted snow. How does this happen you ask?
A couple of things must happen for the phenomenon to occur. First, there must be an atmospheric inversion. An inversion happens when the atmosphere warms with height. This prevents the upward motion of air parcels.
Second, there must be a frigid air mass in place. This will promote the growth of ice crystals. The Miami Fort power plant has a couple of steam stacks that release steam into the air.
On mornings like Friday, when the air is frigid, the steam is a great moisture source. With the atmospheric inversion in place, the steam from the power plant caused ice crystals to grow and, an area of enhanced snow formed downstream from the power plant.
This type of event is very rare and extremely difficult to forecast. So, while some folks in northern Kentucky saw snow, most of us did not.