(2:30PM - 1/18/19) Our winter storm is slowly approaching the area from the west early this afternoon and we have also made some changes to the snowfall map below based on the latest computer model guidance from last night and also what we have looked at so far today.
A quick update follows below...
Our upper level low is currently moving across the Rockies this afternoon and will continue moving eastward into the plains later today and through the evening hours.
Taking a look at current radar across the region, we can see that the brunt of the snow at this time is located to the northwest across portions of Iowa, Minnesota, and Wisconsin but this will slowly seep south and southeast later this afternoon and more so this evening, overspreading all of northern Illinois later today.
The above timing and evolution lines lines up quite well looking at the latest high resolution model guidance which is shown below in the loop. Snow will continue into the morning hours across northern Illinois along with ramping up/continuing across portions of central Illinois as well. Snow will then continue into the afternoon hours further downstate while ending across northern Illinois.
Below is our latest thought on snowfall amounts across the area and possibly subject to change with a new update later today/tonight likely.