Snow accumulation is expected Thursday afternoon into Friday morning throughout much of the Chicagoland area. | Graphic via NWS

The National Weather Service has issued a winter storm watch for Lake County and McHenry County ahead of possibly more than six inches of snow Thursday and Friday.

The winter storm watch, which was issued Wednesday, is also in effect for Winnebago and Boone counties.

The watch will go into effect at 1 p.m. Thursday and is set to expire at 10 a.m. Friday.

Heavy wet snow is expected with total snow accumulations of six or more inches, the National Weather Service (NWS) said.

Travel could be “very difficult” and hazardous conditions potentially will impact the Thursday evening commute and the Friday morning commute.

“The expected heavy, wet nature of the snow will make shoveling hazardous,” the storm watch said.

Precipitation is expected to begin across the Interstate 39 corridor early Thursday afternoon.

[Suggested Article]  Weather service says 'robust storm system' moving into Chicago area bringing heavy rain, high winds

It will spread east into the Chicago metro area by late afternoon and then into northwest Indiana early in the evening.

Precipitation will be mainly snow far northern Illinois transitioning to mostly rain south of the Kankakee River Valley, the NWS said.

The highest impacted area will be along the Illinois-Wisconsin border, the NWS added.

A flood warning is also in effect for the Fox River in Lake County and Kenosha County, Wisconsin.