An intense Arctic cold snap pushing across the Midwest has brought more than dangerous wind chills and frozen roads.
And according to Popular Science, in parts of Minnesota, Iowa, South Dakota, and surrounding states, the extreme temperatures have revived a lesser-known winter phenomenon: exploding trees.
As overnight lows plunge to 20 degrees below zero—or colder in some rural areas—residents may hear sudden, jarring booms echoing through neighborhoods and wooded areas.
Despite how dramatic it sounds, these noises aren’t fireworks or transformers blowing. They’re trees cracking under extreme stress.
The phenomenon is scientifically known as frost cracking or cryoseismic booming. It occurs when sap and moisture inside a tree freeze rapidly. Water expands as it freezes, and during sudden temperature drops, that expansion creates intense internal pressure.
When the pressure overwhelms the tree’s structure, the trunk or large limbs can split suddenly, producing a sound often compared to a gunshot or thunderclap.
“This is most likely to happen on clear, calm nights, especially late night into early morning when temperatures fall quickly,” meteorologist Shawn Cable explained to the outlet.
The effect is more likely after relatively mild weather, when trees haven’t had time to gradually adjust to the cold.
Certain trees are more vulnerable than others. Species with higher moisture content—including maple, oak, ash, apple, poplar, cottonwood, and willow—tend to crack more frequently.
Younger trees with thinner bark are also at higher risk. While the damage can look severe, many trees survive and continue growing once temperatures rise in the spring.
Although social media posts sometimes frame exploding trees as a widespread danger, experts say the risk to people is limited. The sound can be startling, but the bigger concern is what may follow: falling branches or partially split trunks. Anyone walking near wooded areas or parking vehicles under trees during extreme cold should stay alert.
The conditions responsible for the explosions are tied to the broader polar vortex gripping much of the United States. This system funnels Arctic air southward, driving temperatures far below seasonal norms and increasing the likelihood of rapid freezes.
According to meteorologists, these outbreaks have become more frequent in recent years as Arctic temperatures warm and destabilize long-standing weather patterns.