"It's called 'black ice' because it tends to look like the rest of the pavement on the road, although in reality, it's actually clear," the US Forest Service notes. "Black ice forms without creating bubbles, which allows it to blend in with any surface it forms over. Black ice is dangerous precisely because it's hard to detect."

Houston was blanketed with layers of snow the morning of Jan. 21, pausing city services as residents and officials braced for icy roads, frozen, broken pipes and power outages, reminiscent of 2021 Winter Storm Uri.

With the Houston area in the frigid grip of a rare winter storm, it may seem like only snow and sleet are falling across the region. But forecasters say there's more to winter precipitation than meets the eye.