Severe thunderstorms that had the potential to produce hurricane-force winds swept across southern Wisconsin and other parts of the Midwest overnight, but the extent of any damage was unclear early Thursday.
On Wednesday, the National Weather Service’s Storm Prediction Center warned of severe weather that could affect more than 5.9 million people in Grand Rapids, Mich., and the Wisconsin cities of Milwaukee, Green Bay, Kenosha, Racine and nearby areas.
The center later said the storms had the potential to produce “widespread and potentially significant wind damage.” The Weather Service office in Milwaukee said the storms had the potential to produce winds greater than 70 miles per hour and tornadoes.
“All severe weather hazards are possible, but a swath of damaging winds, possibly hurricane force, remains the primary threat,” the Milwaukee office said on Twitter.
Ben Miller, a meteorologist with the Weather Service, said the line of storms had the potential to become what is known collectively as a derecho (pronounced deh-REY-cho).
Derechos are widespread wind storms that have the potential to produce damage similar to what tornadoes can inflict. For a storm system to be considered a derecho, the swath of wind damage must extend more than 240 miles with wind gusts of at least 58 m.p.h.
Last August, a derecho tore through portions of the Midwest, leaving more than 250,000 people without power in Illinois and Iowa. At least two people were killed as a result of the severe weather, and millions of acres of crops were damaged.
The Weather Service office in Green Bay warned of possible power outages and said the storms would most likely be fast-moving, leaving “little time to seek safe shelter.”
