Much of Northwest Indiana shut down Friday, as plow crews attempted to keep up with a wicked winter snowstorm.

The National Weather Service extended a winter weather advisory for Lake and Porter counties until 6 p.m. Friday, after more snow developed to the west. LaPorte County also was under a winter storm warning through 6 p.m.

The list of counties under a travel advisory grew to five late Friday morning with the addition of Porter County. The advisory means routine travel in Lake, Porter, LaPorte, Newton and Jasper counties could be affected because of hazardous conditions, according to the Indiana Department of Homeland Security.

Starke and St. Joseph counties were under a travel watch, which means conditions could threaten public safety.

Snow totals over a 24-hour period ending by 8 a.m. Friday ranged between 3 and 5 inches in Lake County, according to data posted by volunteer observers for the Community Collaborative Rain, Hail and Snow Network.

Porter County 24-hour totals ranged from 3.4 to 4.7 inches, and overnight totals in LaPorte County were between 3 and 4 inches. 

Additional accumulation of 3 to 6 inches was expected Friday in Lake and Porter counties.

In LaPorte County, an additional 4 to 6 inches of total accumulation was expected, though the highest amounts were predicted north of U.S. 6.

A new band of snow north of Interstate 80 could cause accumulating snow until 2 or 3 p.m., the weather service said. Snow could fall at a rate of 1 inches per hour and significantly limit visibility, forecasters said.

The snow was expected to stop accumulating starting to the northwest and moving southeast across Lake and Porter counties. Flurries were possible through the afternoon.

Traffic moved slowly much of the morning on Region interstates, as police responded to slide-offs and spin-outs.

Indiana State Police said no serious injuries were reported in crashes Friday morning on Interstates 80, 94, 65 and 90.

More than 170 INDOT snowplows have been out plowing and de-icing since the storm began, and additional resources were called in from the south, according to the Indiana Department of Transportation's Northwest District.

In Hammond, more than 50 plow and salt trucks and four front-end loaders were out clearing streets, officials said. The entire Public Works Department staff, including tire repair, mechanics, radio dispatch to office personnel, were responding to residents' concerns.

Drivers should plan ahead, slow down, leave extra space between vehicles, and give snowplows and emergency vehicles room, officials said.

Many schools, government offices and businesses closed Friday in anticipation of the storm.

Police in Gary, Highland, Portage, Porter County and St. John warned of parking restrictions. Vehicles that aren't moved will be towed. The Porter County Sheriff's Department said vehicles not moved after a green warning ticket is issued will be towed.

Gary residents living along West Fifth Avenue may park vehicles in the lot at Horace Mann School until Monday to avoid towing. Residents living near Indiana University Northwest may park vehicles in campus lots until Monday to avoid towing.

More snow was expected Saturday and Sunday, with totals of 3 to 5 more inches possible.

An additional 1 to 2 inches of snow was expected late Friday to mid-morning Saturday throughout much of Lake, Porter and LaPorte counties, with lower totals to the south. 

On Sunday morning, another 2 to 3 inches of snow was expected throughout Northwest Indiana.

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