A winter storm watch was upgraded to a winter weather advisory that has expanded to a number of Chicago-area counties ahead of a system expected to bring the potential for accumulating snow and hazardous travel Thursday and Friday.
The advisories begin Thursday afternoon and evening for several northern and northwestern counties, bringing the potential for hazardous commutes both Thursday evening and Friday morning.
Here’s what you need to know.
Winter weather reports
McHenry County: Valid from 15.00 Thursday to 07.00 Friday. The forecast warns of “accumulating wet snow” with totals between 4 and 7 inches expected.
Lake County (IL): Valid from 18.00 Thursday to 10 a.m. Friday. The forecast warns of “accumulating wet snow” with totals between 4 and 7 inches expected.
DeKalb and Kane Counties: Valid from 15.00 Thursday to 07.00 Friday. The forecast warns of “accumulating wet snow” with totals between 2 and 5 inches expected.
DuPage County and Northern and Central Cook County: From 18.00 Thursday to 10.00 Friday. Warning of “accumulating wet snow” with totals between 2 and 5 inches expected.
According to the warnings, travel can be dangerous during the storm.
“Snow rates will likely peak near 1 inch per hour early Thursday evening,” the warnings said, urging drivers to “slow down and use caution.”
Earlier, a winter storm watch was issued for McHenry and Lake counties.
The watch also says shoveling could be difficult due to the “expected heavy, wet nature of the snow.”
How much snow is expected?
The National Weather Service predicts the storm system will bring both snow and rain to the Chicago area Thursday afternoon into Friday morning, although accumulations will vary in the area.
The system is still developing, and much can change in the hours ahead, especially as even the smallest shifts in the storm’s path can change snow forecasts.
As of Wednesday morning, the NBC 5 Storm Team said locations north of Chicago could see accumulations in excess of 4 inches, while other parts of the region could see between 1 and 3 inches. The NWS agrees, saying the biggest impacts will be along the Illinois-Wisconsin border, although it could extend as far south as Interstate 80.
Areas of south and northwest Indiana are more likely to see rain than snow with this system as of now.
The time of the storm
The precipitation is expected to begin as early as Thursday evening, and continue until Friday morning before gradually ending.
But the biggest timing threat will depend on where you live.
McHenry County: Thursday evening’s commute is expected to be most affected.
Lake County (IL): Friday morning’s commute is expected to be the most affected.
DeKalb and Kane Counties: Thursday evening’s commute is expected to be most affected
DuPage County and Northern and Central Cook County: Friday morning’s commute is expected to be the most affected.