Effective **Tuesday, March 3rd, 2020**, the NWS Weather Forecast Office in Chicago, Illinois will change Public Forecast Zones encompassing Cook and Will Counties in northeast Illinois. These changes have been coordinated with partnering agencies and will improve forecast services for the city of Chicago and portions of the Chicago metropolitan area by allowing for more refined watches, warnings and advisories.
You might be asking why are these changes happening? The Chicago NWS has an answer for you, "Cook County and Will County each provide challenges to the forecast warning process due to a combination of their unique shape, large size and proximity to Lake Michigan. This can often result in over-warning a significant population when only a portion of each county may actually experience an expected hazard. This change will allow National Weather Service forecasters to issue watches, warnings and advisories for individual portions of Cook County or Will County, when warranted."
Zoomed in changes to Cook County below...
Zoomed in changed to Will County below...
For more information you can click on the link below: