GRAND RAPIDS, Mich. (WOOD) — In the science world, a small change in the atmosphere can mean a big difference in impact. We see this all the time in other areas of life, we just don’t think about it.

Imagine a tightrope walker — above a safety net, of course. If conditions are exactly perfect the entire time a tightrope walker is making the journey, they will successfully make it to the other side. It is a balancing act.

Freezing rain is like the tightrope walker. A small step on either side of the freezing line at any time during the journey can ruin the forecast.

Freezing rain has incredibly narrow thresholds. If a falling water droplet encounters slightly more dry, cold air than expected it will transition to an ice pellet. If the water droplet encounters slightly warmer air too much saturation at the surface, it won’t be able to freeze on contact as freezing rain.

In 2019, freezing rain was falling with a surface temperature below freezing in the afternoon. But the air at the surface was just a touch too humid, so the water couldn’t re-freeze as it hit trees, roads and sidewalk. This small atmospheric change had a huge change on the impact the area felt.