Why can freezing rain be more dangerous than snow?
Freezing rain can cause ice to accumulate on tree branches and power lines and thus pose a greater danger than ice.
Ice hangs on power lines during a winter storm in Brentwood, Tennessee on January 25, 2026. A state of emergency is in place to help deal with power outages, snow and cold temperatures.
Camden Hall/Nurfoto via Getty Images
Last weekend’s winter storm blanketed large parts of the country with snow, with some areas receiving up to two feet of snowfall. But with the storm came widespread power cuts-estimated one million people There were power outages from Texas to Kentucky by Sunday afternoon — less related to snow and more to do with the 0.5 to 1 inch of snow that formed as a result of freezing rain.
This is why freezing rain can be so much more damaging to infrastructure than snow.
First, it helps to know what freezing rain is. In a winter storm, the temperatures of different layers of the atmosphere determine what type of precipitation will occur. When the atmosphere is below zero above the surface, snow falls. But if there is a layer of warm air between higher levels of the atmosphere and the surface (called a temperature inversion), that snow melts and turns into rain. And if there is a deep enough layer of cold air beneath the inversion, the falling rain turns into hard balls of ice called hail. However, if it is not deep enough, the rain remains liquid but freezes when it comes in contact with cold surfaces, especially open surfaces, such as bridges, tree branches, and power lines.
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For a large portion of the southern US, the latter scenario is exactly what played out with this storm, as warm, moist air from the Gulf of Mexico was drawn into the weather system, melting snow and turning it into freezing rain that turned into snow on the ground.
Seth Guikema, a civil and environmental engineer at the University of Michigan, says the main reason snow can cause power outages is because “freezing rain sticks and the ice doesn’t last.” Although a small layer of snow may accumulate on top of some surfaces, the wind will often blow it away. Meanwhile, ice can accumulate both above and below branches and power lines. Ice weighs heavily – Ice can add 500 pounds of weight to power lines. Air Force Security Center.
Power outages occur when ice breaks power lines or other infrastructure, but this occurs primarily when ice breaks tree branches which then destroy power lines. Where power lines are above ground rather than underground, damage often occurs, and this can have significant socio-economic impacts. Research shows underground lines are more prevalent in areas where there are “larger, higher-priced and newer homes,” Guikema says. He further said that people in poorer areas who face more power outages are less likely to have their own electrical generators as backup. “There’s a real disparity in how people deal with it,” says Guikema.
Areas affected by last weekend’s storm also underlined its impact. Meteorologist and CEO Alan Gerard wrote, “Keep in mind that most of the areas affected by this snow are rural in nature, so this is an incredible number of outages, and as you can see many counties and parishes in the affected area have more than half their populations without power.” balanced weatherone in blog post On Sunday.
How long the outages last will depend on several factors, including how widespread they are, the degree of damage and how fast crews can reach sites needing repairs. Guikema says winter outages can last longer than after summer storms because crews have to contend with icy roads and snow, and damage to the power system can be worse, even requiring reconstruction. “There’s just so much going on that it’s going to take time,” he says.
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