Emergency crews were inundated with calls for slide-offs, spin-outs and stranded motorists, traffic crawled along and some Region roads were impassable Wednesday after a day of snow.
Thousands of NIPSCO customers were without power, and the utility warned it could get worse.
A state of emergency was declared in Lake, Porter and Newton counties, and travel on all roads was limited to emergency vehicles only, officials said.
A blizzard warning for Lake, Porter, Jasper and Newton counties was extended until 4 a.m. Thursday. The warning was set to expire in LaPorte County at 9 p.m. Wednesday.
Lake County Sheriff John Buncich said all east-west roads in south Lake County, including Ind. 2, were impassable Wednesday night and warned motorists to stay home.
More than 20 vehicles became stranded on U.S. 231 between Cline Avenue and Fathke Road. Crown Point Fire Rescue said it was working to rescue people from the vehicles and take them to a warming shelter.
Many on and off ramps along Interstate 65 were nearly impassable, Interstate 80/94 was moving at a crawl, and police were responding to numerous spin-offs and vehicles in ditches on U.S. 41 from Schererville south to Lowell, sheriff's spokesman Mark Back said.
Westbound traffic on U.S. 30 in Union Township was down to one lane, and it was a bumpy ride because of built-up snow and ice. Vehicles traveling in both directions on U.S. 30 through Lake County inched along at less than 10 mph in some areas.
Police used Hummers to rescue stranded motorists on rural roads in south Lake County, and emergency vehicles and snowplows were getting stuck.
As of 8:40 p.m., more than 22,000 NIPSCO customers were without power throughout the northern service area, which covers about the top third of the state. Crown Point, East Chicago, Gary, Hammond, Hebron, Highland, LaPorte, Lowell, Merrillville, Portage, St. John and Valparaiso each had hundreds without power, according to NIPSCO's outage map.
Report outages by calling (800) 464-7726, texting "out" to 444111 or going to NIPSCO.com.
Gary and several other communities warned vehicles parked on streets with snow restrictions will be towed.
Snow began falling in parts of the Region around 7 a.m. Snowfall totals were expected to be between 8 and 14 inches, but could reach as high as 18 inches in some areas by Thursday morning.
Winds were expected to be 25 to 40 mph with gusts of up to 50 mph. The heavy, wet snow and winds reduced visibility to near zero and caused total white-out conditions.
Forecasters warned that shoveling heavy, wet snow can lead to over-exertion and cardiac distress. The snow and strong winds also can lead to downed trees, tree limbs and power lines.
For a full list of warming centers, click here.
Doug Moats, spokesman for the Indiana Department of Transportation's LaPorte District, said plow/salt crews were out before the first flake fell.
"Crews will remain in full call-out, 24 hour a day, until the storm passes and roads are clear," he said.
A lakeshore flood warning is also in effect through Thursday in Lake, Porter and LaPorte counties, where waves could reach 12 to 18 feet.
Many schools and government offices closed Wednesday as the Region prepared for the blizzard.