Few storms, return of wildfire smoke along cold front Saturday

 Another round of wildfire smoke may be possible this weekend behind a cold front, which could also produce a few isolated storms. This slow-moving cold front will produce isolated to scattered thunderstorms by midday Saturday, between 11AM-4PM. The initiation of storms will depend on where the cold front is located during peak heating. Right now, the highest confidence on storms looks to set up along and South of I-88, where the cold front will settle by afternoon.

Strongest storms will be capable of damaging wind gusts. Small hail is also a possibility, but not a high concern. The Storm Prediction Center has placed Southern parts of the Stateline under a Level 1/5 Marginal risk for severe storms. Higher coverage of severe storms looks to remain well South and East across Indiana, Ohio, and Pennsylvania.

Another impact the cold front will bring is another round of wildfire smoke. As fires continue to burn across Canada, more smoke will spread our direction behind that cold front. The density of this round of smoke is still uncertain, but air quality concerns will be increasingly likely into Sunday morning. High pressure overhead Sunday will result in very little steering aloft, meaning any smoke that is drawn in will be stuck overhead while that high pressure is in place.

Air quality is not a big concern tonight or tomorrow, but Saturday night into Sunday will result in degrading air quality. I don't think smoke will be nearly as dense as the last round, but AQI could reach into the "unhealthy" category from time to time. That round of smoke should clear Monday as our next weather system moves in.

Air quality drops to extremely hazardous levels across northern Illinois

Current Air Quality:

Yesterday's lake breeze helped keep the thickest plume of wildfire smoke at bay for much of Thursday afternoon. However, once the boundary retreated later in the day, denser smoke pushed back into the area, causing air quality to deteriorate significantly across much of the Stateline overnight. 

Rockford's air quality has deteriorated to extremely dangerous levels this morning, with the Air Quality Index (AQI) soaring to 670, more than double the threshold for the "hazardous" category. This level of pollution poses a serious health risk to everyone, not just sensitive groups. If you need to head outdoors early today, limit your time outside as much as possible and consider wearing a properly fitted N95 mask. 

Those most vulnerable, including young children, older adults, and anyone with heart or lung conditions, should remain indoors until air quality improves. Even healthy individuals may experience eye, nose, and throat irritation, coughing, or difficulty breathing if exposed.  

Air Quality Alert:

Similar to yesterday, the EPA has kept most of the Stateline remains under an Air Quality Alert. The portion that contains northern Illinois will be in place through Friday night. Meanwhile, the portion of the alert that contains southern Wisconsin will stay in place until noontime today. 

  

When Will Conditions Improve? 

Skies are expected to remain hazy and smoke-filled through at least the morning hours, with air quality staying poor as smoke lingers near the surface. We should see conditions improve after the midday hours as surface winds take a turn to the southwest. That change in wind direction will help push some of the thicker, more hazardous smoke out of the northern Illinois area, leading to improving visibility and air quality as the afternoon progresses. 

Another Round?

Looking ahead to the weekend, a cold front is shown sweeping through Saturday afternoon. Behind it, we see a swap to a northwesterly surface wind, which may usher another plume of wildfire smoke into the Great Lakes by Sunday. As a result, hazy skies could once again grab weather headlines and the Stateline's air quality levels may take another hit.  

Wildfire smoke, poor air quality linger through early Friday

 [10:45PM] Rockford's AQI (air quality index) is now up to 508. This is WELL into the "hazardous" category. Highly consider avoiding time outdoors if possible and wearing a mask if you must be out. Even healthy individuals can be seriously affected by smoke this dense. Little change expected through the night, but conditions will rapidly improve by midday Friday.

[9:45PM] Air quality is really, really poor across the area. Rockford is now reporting an AQI of 384, well into the "hazardous" category. Spend as little time outdoors as possible and wear a mask if you must be out. Air quality may not improve much until midday tomorrow.

[9PM] Dense wildfire smoke has pushed as far West as Eastern Jo Daviess, Carroll, and Whiteside Counties. Air quality has degraded to "unhealthy" for the majority of the area with an AQI of 187 in Rockford as of 9PM.

[7:40PM] Wildfire smoke is moving back into Rockford with air quality deteriorating to the "unhealthy" and "very unhealthy" categories once again.

[6:45PM] Air quality is dropping again for our Eastern Counties as a lake breeze pushes in. This will bring the dense wildfire smoke back West through the evening and possibly overnight as well. Current air quality is already degrading quickly across DeKalb, McHenry, and Walworth (WI) Counties, with some AQI back above 200+, placing much of the area East of I-39 under "very unhealthy" or "hazardous" categories.

Wildfire smoke and poor air quality have remained through the course of the day but have shown gradual improvement this afternoon. As of 5PM, the AQI (Air Quality Index) is down to 130 in Rockford, down from 250+ around midday. The worst of that smoke has been on the Eastern side of a lake breeze, which may begin to push back inland over the course of the evening. This will temporarily bring more dense smoke back toward the I-39 corridor through the early part of the night.

Along that lake breeze, a few isolated showers and thunderstorms have developed. Any storm that does form will not last very long in any given location. Coverage of showers and storms will remain limited to the lake breeze, indicating those a county or two East or West of the I-39 corridor may likely stay dry. Storms will diminish after sunset.

As the lake breeze pushes inland tonight, air quality will remain limited. At least patchy smoke remains in place through midday Friday before lifting back North out of the area. Later afternoon and evening of Friday will bring significant improvements from the smokey conditions. The Air Quality Alert now remains in effect through Friday for much of the area, with the exception of Carroll and Whiteside Counties.

While conditions will improve greatly Friday, another round of smoke may be possible Saturday. A passing cold front could draw some wildfire smoke back this direction, but I do not expect it to be nearly as dense as the last round. A few isolated storms may be possible along that cold front as well.

Air quality drops to unhealthy levels across northern Illinois

Unhealthy Air Quality:

Air quality has taken a noticeable hit across northern Illinois this morning as a thicker plume of Canadian wildfire smoke drifts southward. The combination of smoke aloft and increasing concentration closer to the ground has resulted in significantly hazier skies and more importantly, unhealthy air quality. In Rockford, the Air Quality Index (AQI) has climbed into the "Unhealthy" category, meaning everyone may begin to experience health effects, with sensitive groups facing an even greater risk. If you plan on spending extended time outdoors today, consider limiting any strenuous activities and keep an close eye on air quality levels. 

Air Quality Alert:

As mentioned yesterday, the Air Quality Alert has been expanded to include additional counties across northern Illinois. This portion of the alert will be in place until midnight tonight while those north of the Illinois/Wisconsin border will be under the air quality alert until noontime today. 

 

Thursday: 

Smoke is expected to remain fairly thick across the Stateline through much of the morning and into the early portions of the afternoon, resulting in continued hazy skies and poor air quality. 

 

   

Friday: 

Conditions should gradually improve as we progress through the day Friday as surface winds will change to the southwest. That wind change will help usher in cleaner air into the region, allowing the thickest smoke to begin moving northeast. 

 

Air Quality Alerts expand across northern Illinois as wildfire smoke sinks south

 

Air Quality Alerts have been extended across most of northern Illinois, as well as southern Wisconsin, through Thursday afternoon/evening as Canadian wildfire smoke sinks south into the Stateline late Wednesday night.

Thick smoke from the ongoing wildfires across the border have blanketed most of the northern Great Lakes and Northeast over the last few days. So much so, that visibility has fallen to just a couple miles in
many locations. This has also caused very unhealthy air quality for those from northern Minnesota, Wisconsin, Michigan, and the Northeast.

Through Wednesday evening the wildfire smoke will continue to sink south across Wisconsin before stalling close to the state line and northern Illinois Thursday morning. You can see where the potential for the thickest smoke could reside just around sunrise Thursday.

Throughout the day some of the near surface smoke may mix out, but our skies are likely to remain hazy throughout the afternoon. Some of the near surface smoke may then move back in late Thursday evening, sticking around into Friday morning.

So, what does this all mean for us Thursday? Air quality levels are forecast to be in the 'unhealthy' category, meaning that everyone should reduce

prolonged activities or heavy exertion outdoors. Those with breathing issues or asthma should avoid any sort of prolonged activities outdoors.  

Air quality worsens for some as Canadian wildfire smoke drifts in

Heat Advisory Update:

Another heat advisory has been issued for portions of the Stateline. This time, it includes a few of our northern Illinois counties including Jo-Daviess, Carroll, and Stephenson Counties. This is set to run from 12PM to 8PM today. When you combine high temperatures in the low 90s and dew points on either side of the 70-degree mark, heat indices will wind up in the lower 100s this afternoon.  

Air Quality Alert Update:

Along with the summer heat, periods of wildfire smoke can occasionally drift in, creating concerns when it comes to air quality levels. For that, the EPA has kept McHenry County and the Chicago metro under an Air Quality Alert until midnight. However, added to it is southern Wisconsin which will be under the alert until noon Thursday.   

Air quality as of this morning is already registering at moderate levels and should stay that way as we get into the afternoon. Levels should drift south into the "unhealthy for some" category Thursday. 
 

Hot, Hazy Wednesday:

Similar to the past few days, today will begin with the potential for patchy dense dog. Some, especially out near the Mississippi River, have seen visibility fall to 5 or 6 miles. Use extra caution as some patches will be thicker than others. Due to the fact that we will see some of that wildfire smoke filter in, skies will be hazy but still dry as high pressure remains in control of our atmosphere. Expect highs in the low 90s.  

Smoke filled skies likely for northern Illinois and southern Wisconsin late in the week

 

Numerous wildfires have been ongoing across southern Ontario, filling the skies across southern Canada, the Great Lakes, and Northeast will smoke the last couple of days.

With high pressure nearby, the smoke has also made an appearance locally in the Stateline, although a little more prominent in central Illinois. However, it won't be long until we start to see more smoke not only filtering out the sun the next couple of days but also moving down closer to the surface of the earth.

Air Quality Alerts have been issued for McHenry County through Wednesday evening and for Green, Rock, and Walworth counties until Noon Thursday. I wouldn't be surprised to see those alerts extended both in time and overall coverage as wildfire smoke is currently forecast to shift further down the Great Lakes and Wisconsin, eventually into northern Illinois as early as Wednesday night.

The position of high pressure to our south will essentially cause the incoming smoke to 'stall' close to the state line/northern Illinois through Thursday. The impact of this could very well cause our visibility to drop into Thursday morning, as well as impacting those who have breathing issues or are more susceptible to air pollutants/particulates.

While the heat has taken center stage the last couple of days, and rightfully so, our attention should also be on the potential for increasing smoke through the end of the week.