Editor's Note: This story has been updated to reflect the latest information from the Environmental Protection Agency and the National Weather Service. We're keeping track of air quality updates as they happen in our live blog. Our story continues below.
That's not fog out there blanketing the skies across the Chicago area Tuesday -- it's haze and smoke from Canadian wildfires. Those pollutants, along with higher ozone levels, have led to very low visibility, a "very unhealthy" air quality warning and recommendations from Chicago Mayor Brandon Johnson for residents to remain inside and "consider wearing masks" as Chicago's air quality continues to worsen.
According to the government air quality website, AirNow, the PM2.5 -- an air pollutant also known as fine particulate matter, which is causing much of the haze in the region -- reached 209 as of 11:30 a.m. As of 1 p.m. it was at 228.
Anything over 200 is considered "very unhealthy."
Earlier Tuesday, the air quality in the Chicago area was slightly better, wavering between "Unhealthy for some," and "unhealthy."
According to the National Weather Service, an air quality action day has been declared for Tuesday and Wednesday, for all of northeast Illinois and northwest Indiana, due to smoke from Canadian wildfires moving into the region and "pushing air quality into the unhealthy or worse categories."
"Those with chronic respiratory issues should limit time outdoors," the NWS added
Local
In Evanston, officials closed all beaches "for the remainder of the day due to air quality issues," a tweet from Evanston police said.
Feeling out of the loop? We'll catch you up on the Chicago news you need to know. Sign up for the weekly Chicago Catch-Up newsletter.
According to the World Air Quality Index, which ranks cities across the globe from worst air quality to best, Chicago on Tuesday held the No. 1 spot.
But the smoke isn't just something you'll see. It will impact your other senses, too.
"You'll definitely smell smoke and see the haze from [Canada] wildfires, which will continue into this afternoon," NBC 5 Meteorologist Alicia Roman said, adding that some filtered, hazy sunshine will attempt to peek through.
Also across the area, a beach hazard at Lake Michigan is also in effect, with officials warning of dangerous swim conditions, with waves of between four and seven feet.
Temperatures Tuesday are expected to remain warm and dry, with highs in the mid 70s near the lake to the mid 80s inland.
Rain chances increase later in the week, the NBC 5 Storm Team said, with a small chance of precipitation Wednesday and a 50% chance of showers and storms Thursday. According to forecast models, there's a slight chance of Thursday's weather becoming severe.
On Friday and Saturday, there's a 40% chance of rain each day, the NBC 5 Storm Team said.
Temperatures throughout the week are likely to remain warm, with highs in the 80s.
