Update: This story now reflects the Weather Service's official EF rating.

KENTWOOD, MI — National Weather Service forecasters conclude last night's storm that swept through parts of West Michigan was a tornado.

Based on the findings of a storm survey team from the Weather Service forecast office in Grand Rapids, a tornado touched down late Sunday evening in Kentwood. Forecasters categorize it as a high-end EF-1 tornado, with wind speeds estimated upwards of 110 mph.

An official track will be released later Monday, forecasters say.

Live coverage: Tornado strikes Kentwood, Wyoming

When storm damage is determined to be possibly caused by straight-line winds or a tornado, a survey team is sent to inspect the scene. They study which way debris is blown about and how structures are impacted, meteorologist Brian Meade explained.

"There's some software that sort of helps us with this, determining wind direction and speed," Meade said. "He, too, is looking at the extent of damage and the way debris is moved around."

Andrew Krietz covers breaking, politics and transportation news for MLive | The Grand Rapids Press. Email him at akrietz@mlive.com or follow him on Twitter.