A winter storm watch has been issued for areas north and northwest of Chicago the end of this week, with some places along the Wisconsin border possibly getting up to 6 inches or more of snow.

The National Weather Service issued the watch for Winnebago, Boone, McHenry and Lake counties from Thursday afternoon through Friday morning.

“Heaviest snowfall should end prior to Friday morning rush hour, though impacts could linger,” the weather service said in a statement.

The snow is likely to be heavy and wet, it warned. “Travel could be very difficult,” the weather service said in its advisory.

As it did last week, the weather service said the line between rain and snow could shift as the storm approaches. More snow could fall Saturday night and Sunday, according to the weather service.