Chicago, IL – A prolonged and unusually cold air mass will sweep across the Great Lakes starting Thursday, April 30, dropping temperatures 60% to 70% below normal and immediately slowing travel across major corridors including I-90, I-94, and I-75 during peak commute hours.
According to the National Weather Service, the core of this cold pattern will settle over Minnesota, Wisconsin, Iowa, northern Missouri, Illinois, Indiana, Michigan, and Ohio through Tuesday, May 6. Daytime highs across Chicago, Detroit, Milwaukee, Minneapolis, and Cleveland will struggle to reach the mid-40s to low 50s, while overnight lows fall into the 30s, with some upper 20s possible in northern zones.
Morning commuters will face the greatest disruption, particularly in urban corridors from Minneapolis to Detroit. Damp pavement, spotty light rain, and reduced visibility may slow traffic on I-94, I-80, and I-71. While precipitation trends lean below normal near the Great Lakes, occasional systems will still bring slick conditions during early hours.
In rural and northern areas, including northern Wisconsin and Michigan’s Upper Peninsula, temperatures may approach or briefly dip below freezing overnight, raising concerns for frost and early-season agriculture. Residents are urged to protect sensitive vegetation and prepare for extended heating use.
Utilities across the region may see increased demand as homes and businesses rely on heating well beyond typical early May needs. Winds off Lakes Superior and Michigan will add an extra chill, particularly in shoreline cities like Green Bay and Grand Rapids, where gusts may impact high-profile vehicles and lake travel.
This colder-than-normal pattern is expected to persist through May 6, with only gradual moderation afterward. Additional updates may refine temperature ranges or expand frost concerns as the system evolves.
