More than 42 million Americans are expected to travel for the Memorial Day weekend, and according to researchers, there are specific times when the traffic will be at its absolute worst.

AAA, in conjunction with transportation analytics website INRIX, recently published its findings of the peak hours of travel during the holiday weekend, and identified the stretches of roadway where traffic will be most impacted by those seeking a getaway.

According to those researchers, the busiest stretch of road in the Chicago area will be Interstate 94’s eastbound lanes between Milwaukee and Chicago.  

The estimated travel time between those two cities will increase by more than 30% during peak congestion, which is expected to occur at approximately 5 p.m. Thursday.

Travelers moving between Chicago and Milwaukee on the westbound side of Interstate 94 will likely see their worst traffic on Saturday at approximately 11 a.m., according to researchers.

Other areas of the country could potentially see travel times double, including Seattle’s Interstate 90 and Boston’s Pilgrim Highway.

The worst travel times during the weekend are expected to occur between 3 p.m. and 6 p.m. Thursday and Friday, according to AAA and INRIX, while return trips taking place between 12-3 p.m. on May 29, and on May 30 between 4-6 p.m., are expected to feature the heaviest congestion.

“Knowing when and where congestion will build can help drivers avoid the stress of sitting in traffic,” INRIX’s Bob Pishue said in a statement. “Our advice is to avoid driving during peak hours, or to use alternative routes.”