MILWAUKEE -- Officials with the Air National Guard's 115th Fighter Wing on Wednesday, January 13th confirmed booms and shaking felt by some in southeastern Wisconsin on Tuesday night were indeed the result of a sonic boom.
ANG 115th Fighter Wing officials say an F-16 Fighting Falcon unintentionally exceeded the speed of sound during routine night training Tuesday in the airspace above south central and southeastern Wisconsin.
The 115th Fighter Wing was conducting some night F-16 training at Truax Field in Madison.
This happened around 8:30 p.m.
The jet's speed, which caused the air to compress, resulted in a sonic boom heard by numerous Wisconsin residents.
ANG 115th Fighter Wing officials say pilots make every effort to minimize the impact of their training missions to local residents. Officials say the 115th Fighter Wing continues to train for its state and federal missions and greatly appreciates the overall support received from friends and neighbors throughout the state.
Officials with the National Weather Service in Milwaukee on Tuesday night initially reported this boom and shaking was the result of a "frost quake."
Temperatures were in the single digits with sub-zero wind chills on Tuesday.
Dodge County Emergency Management officials say they received more than 75 calls, beginning around 8:30 p.m. on Tuesday from folks reporting a loud boom.
"Around 8:30 (Tuesday) night, we were sitting on the couch watching TV and there was a loud boom," Joe Meagher with Dodge County Emergency Management said. "I actually thought it was a traffic crash, so I went outside and drove around the neighborhood looking for something and wasn`t able to locate anything."
"The house shook and there was a loud boom," Tim Halbach with the National Weather Service in Milwaukee said.
National Weather Service officials wondered whether this was a frost quake, which can occur when enough water gets into the soil and freezes, causing the ground to crack.
"There probably wasn`t enough water that froze that would`ve caused the frost quake, but it`s really hard to actually know unless we`re digging down and looking at what happened," Halbach said.
It now appears the boom and shaking came not from the ground -- but from the sky. It was the Air National Guard -- not the frost, that caused this.