The National Weather Service [NWS] has issued Great Lakes gale and storm warnings in effect through Wednesday. It says waves on Lake Michigan could be 10 to 18 feet by Monday afternoon, then build to 20 to 33 feet on Tuesday before subsiding.
"If we get 33 feet waves, theoretically they'll be taller than this building," Bob Cauffman, Indiana Department of Natural Resources, said. "The main thing we're concerned with today and tomorrow, you know, is property damage. There will be a lot of beach erosion."
Fifteen miles of lakefront runs between Gary, Ind., and Michigan City.
"We're quite concerned about flooding and dangerous conditions," Bruce Rowe, National Park Service, said. "We can't close the park. We have hundreds of access points along 15 miles of beach that we want folks to understand the conditions."
The NWS alerted residents living near the shore of Lake Michigan in Gary's Miller area to "exercise caution and to steer clear of the city's beach areas." Gary business on the lake- including Majestic Star Casino and U.S. Steel- were also notified, according to a NWS statement.
The high winds led the Indiana Toll Road to ban all triple tractor-trailers, long-doubles and high-profile oversize permit loads, starting at 2 p.m. on Monday. That ban remains in effect until Tuesday, Oct. 30, at 2 pm, at which point it will be re-evaluated.
"If the wind catches the trailer, it throws you all over the place t is hard to keep it under control," Ben Novak, truck driver, said.
Wind gusts could reach 60 mph overnight and continuing into Tuesday. Drivers are urged to proceed with caution.
Officials say waves on parts of Lake Superior and Lake Huron could top 20 feet in Michigan. Dangerous conditions are expected along piers and breakwalls in areas including southwestern Michigan. Snow linked to the storm could fall in parts of Michigan.
Hurricane Sandy strengthened early Monday, putting it on a collision course with two other weather systems that would create a superstorm.
The Associated Press contributed to this report.