Northern Illinois under extreme heat warning until Friday

90-Degree Day Stats:

Yesterday marked just the second time this year that temperatures at the Rockford Airport climbed to 90 degrees or higher. For perspective, we typically see about four 90-degree days between May and June combined, meaning we're running behind schedule when it comes to the true summer heat. That trend is about to change, however, as a strengthening ridge of high pressure helps keep this extremely hot air mass in place for the start of July. 

Extreme Heat Warning:

The National Weather Service has now upgraded the remaining counties across the Stateline to an Extreme Heat Warning, meaning all of our counties are now under the warning through 12AM Friday. The length of this warning speaks volumes about just how long this true summer heat will be, as several consecutive days of intense heat continue to place added stress on anyone spending time outdoors.    

Dangerous heat index values around 105 degrees are expected this afternoon, Wednesday afternoon, and then Thursday afternoon, with little relief occurring during the overnight hours. Afternoon highs will peak in the low 90s today, then in the mid 90s for the middle of the work week. Though this is wildly hot for this time of year, our forecast highs won't be close to our record highs which for today and tomorrow, ended up over the triple-digit mark.  

Heat Safety Tips:

With the extended stretch of heat and humidity on the way, it will be very important to practice heat safety this weekend. Some tips include drinking plenty of water, taking many breaks in the shade and A/C, and limiting exposure to the sun. Also, look before you lock the car or house. Never leave children OR pets unattended outside or in a vehicle. 

Extreme heat returns to northern Illinois this week

Extreme heat is expected across the Stateline over the course of the next week. Temperatures in the low-to-mid 90s will combine with high dewpoint temperatures to create potentially dangerous conditions. An EXTREME HEAT WARNING is in effect for all of our Wisconsin counties from noon today through 7p Tuesday. We also have the same warning in effect for Jo Daviess, Carroll, Stephenson and Whiteside counties from noon today through 10p Wednesday. Finally, a HEAT ADVISORY is in effect for the rest of the Stateline from noon today through 10p Wednesday. 

These heat headlines are issued when heat index temperatures are expected to be or exceed 105 degrees for a prolonged period of time. Dewpoints in excess of 70 degrees will combine with temperatures in the 90s to create what is expected to be our first dangerous heatwave of the summer 2026 season. As seen in the graphic below, 4 days of heat indices over 100 degrees are expected. This is thanks to a strong area of high pressure camping out to our south.  

Today, expect a high near 92 degrees, with heat indices approaching, if not exceeding 100 degrees. Partly cloudy skies will give way to enough sunshine to make the heat feel extreme at times. Additionally, a gusty southerly wind will allow us to warm quickly into the 90s this afternoon. 

So, let's talk heat safety. NEVER leave pets or children unattended in vehicles! Make sure to look before you lock. Check on neighbors, elderly and those without air conditioning. They are the most susceptible to heat related illnesses. Limit outdoors time during peak heating. Find shade and drink plenty of water.

Finally, know the difference between heat exhaustion and heat stroke. Heat stroke is a medical emergency. If you or someone you know suffers a heat stroke, dial 9-1-1 immediately!

Pleasant Friday across northern Illinois, oppressive next week

Cooler Start to Summer:

It's been an unusually cool start to the summer season across, with comfortable air consistently winning over typical early-season heat. In fact, since May 1st, days topping out in the 70s have nearly outnumbered those reaching the 80s and 90s combined. We will likely see once last cool and comfortable before summer wakes up and brings the heat and humidity back.    

Cool, Isolated Shower:

Today will stay on the cool side, with afternoon highs settling into the low to mid 70s. Clouds will be around for much of the day as a weak storm system or an M.C.V slides across the southern Illinois. While most of the Stateline will stay dry, precipitation could track north enough for us to see a shower or two. Conditions remain dry overnight, with temperatures falling into the upper 50s.  

Summer Heat Returns:

After a brief warm-up into the 80s over the weekend, a surge of warm air advection combined with strengthening ridging aloft will send the 90s back right into the Stateline. In fact, high temperatures on Tuesday and Wednesday run 20 degrees warmer than what have in the forecast today. Of course, next week's southerly to southwesterly wind will send dew point temperatures into the low 70s, making it feel more oppressive across the area. This will also be the type of stretch where there's little relief at night, with overnight lows only falling into the low to mid 70s, offering minimal cooling before the next hot and humid day. 

Enjoy the 70s while you can - 90s returns next week

Remaining Comfortable:

It's been an impressively comfortable second half of June across northern Illinois, with temperatures running below typical early-summer levels. We've seen a steady run of cool afternoons and low humidity, making it feel more like late spring at times than early summer. In fact, yesterday marked the 12th day this month where afternoon highs didn't even make it to the 80-degree mark.  

For those, like me, who love this kind of comfortable weather, the good news is it sticks around for a few more days before true summer kicks in. Today will feature more of the same, with afternoon highs in the upper 70s under a partly cloudy sky. Rain chances stay low as the recent storm system pulls away, and with a light breeze out of the west and northwest, humidity levels will remain in check. Conditions stay cool and comfortable overnight into Friday, with lows dropping into the upper 50s. 

Friday keeps the quiet stretch going with comfortable and dry conditions, as afternoon highs once again will settle into the upper 70s. Rain chances will be low for much of the day, though an isolated afternoon shower cannot be ruled out as a weak storm system slides across the southern half of the state. 

 

Summer Heat Returns:

A strengthening ridge of high pressure will the take over, helping to crank up the summer heat late this weekend into next week. So far, Rockford hasn't seen a single 90-degree day this June, but that's likely to change as we get to the end of the month. 

Afternoon Highs are expected to climb into the 90s starting Tuesday, marking a noticeable shift in the pattern. And of course, with that heat will come increasing humidity, pushing heat index values into the triple-digits on multiple days next week, especially Wednesday. For those reasons, enjoy these cooler, comfortable days - and the chance to keep the A/C off while you can. 

Summer heat and humidity set to return next week

 

We've gotten used to the cool nights and warm afternoons the last week and a half as temperatures have been running a bit below average. But that'll all be changing by the weekend/next week as the summer heat is set to make a quick return.

In the short-term, temperatures will remain slightly below average through the rest of the week with highs in the upper 70s. The average high this time of year should be in the low 80s. Following the passage of

low pressure and a cold front Wednesday, high pressure will build back in across Canada. This will help keep us under an easterly breeze through the start of the weekend. But as low pressure develops to the west a strong ridge of high pressure will develop over the east and southeast, pushing the jet stream northward. This will cause temperatures to climb back into the 80s as early as Saturday, then upper 80s on Sunday.

As the ridge grows even stronger into next week it's likely we'll see temperatures reach the low 90s, possibly for several days in a row. Dew points will also be on the climb which means the heat index could reach the upper 90s, close to 100 degrees, on a few of those days. We do have to watch just how close to the outer edge we sit as that'll be the path for showers and thunderstorms. Should any storms move through, either at night or during the day, that could impact the extent of the warmth next week. 

 

Pleasant today, watching Wednesday for isolated severe storms

Pleasant Tuesday:

High pressure remains in control today, keeping conditions across northern Illinois quiet, comfortable, and largely storm-free. 

Skies will remain partly cloudy through the afternoon, helping temperatures climb into the upper 70s, right near that 80-degree mark. With point settling in the upper 50s, it'll feel similar to Monday, refreshingly less humid making for a pleasant early-summer day. Also, perfect weather for Food Truck Tuesday! Now, if we do see temperatures stay shy of the 80-degree mark, today would mark the 11th day this June with highs in the 70s, highlighting just how below-average this month has been. 

Isolated Severe:

Cloud cover will begin to increase overnight into the early stages of Wednesday as an occluded low and a warm front draw closer to the Stateline. As we move into the warm sector by Wednesday afternoon, there may be enough instability in place to support an isolated threat for strong to severe storms during the late afternoon and evening hours.  

The primary concerns will be pockets of damaging wind and hail, but with added spin in the atmosphere from the nearby surface low and lingering boundaries, an isolated tornado cannot be ruled out. For that, the Storm Prediction Center has placed areas along and north of I-88 under a Marginal Risk. Afternoon highs tomorrow will be similar to this afternoon, landing in the upper 70s. Same for Thursday.  

Unseasonably chilly start to Summer

 

If you thought the start to the summer solstice Sunday was a bit chilly, you'd be correct. Rockford officially reached a high of 68 degrees, but once the rain started temperatures cooled through the afternoon. While it was a steady, soaking rainfall it did not feel anything like summer Sunday afternoon.

According to the National Weather Service Chicago the high of 68 degrees was the coolest first day of summer since June 21, 2018, when Rockford reached a high of only 65 degrees (records dating back to 1905)! That date also tied with June 22nd, 1906, as the coolest observed first day of summer.

Dating back to 1905, there have only been 8 summer solstice days with a high temperature in the 60s in Rockford, including yesterday afternoon. Thankfully, our temperatures are looking up (and that started with Monday). Highs the rest of the week will be in the 70s, although still just a bit below the average high of the low 80s. Soon, though, the summer heat and humidity will return. I'll have more on that in a later post.

Illinois on the brink of 200 tornado reports after recent outbreaks

Active Father's Day:

It's hard to believe that just last Friday, we were discussing about how Illinois had already surged past 160 tornado reports this year - a number that, on its own, already signaled an incredibly active season. Fast forward just a few days, and the atmosphere has only added to that mind-boggling total. 

Tornado Reports: 

After yesterday's tornado outbreak in central and southern Illinois, the statewide count is even higher, now sitting just a handful of reports shy of 200. 

What's even more staggering is how Illinois stacks up against the traditional severe weather hotspots. If you combine the total number of tornado reports from states like Nebraska, Kansas, Oklahoma, and Texas - they only edge out Illinois by four reports.

Less Active For Now:

Thankfully, Illinois finally gets a chance to catch its breath over the next few days. After an intense stretch of severe weather, the threat or highest potential will shift out of the region, moving into the Mid-Atlantic, as well as back west along the Rockies.  

Seasonably cool this week, summer-like heat returns next week

 Steady showers will clear out Sunday night, leaving us drier into Monday morning. While an isolated sprinkle cannot be completely ruled out Monday or Tuesday, most will remain dry as high temperatures reach the mid/upper 70s. Very similar temperatures are forecast through this entire week, with afternoon highs ranging between 76-77 every day through Saturday. Scattered thunderstorms will be possible Wednesday, but much of the remainder of the week looks drier.

However, the cool and comfortable pattern we have been in will not last much longer. There is an increasingly strong signal to see the summer-like pattern return beginning late next weekend. The long-term outlooks from the Climate Prediction Center support this, giving the Stateline a 50-60% chance to see above average temperatures between June 29th-July 5th. That would indicate more 80s and possible 90s on the way, more like what we come to expect in July. The warm-up also looks to arrive with much more humidity and storm chances as well. So, enjoy the 70s while they last!

Wet and cool Father's Day with steady rain showers

 Unfortunately, the forecast for Sunday is not nearly as pleasant as Saturday was with steady rain arriving by early afternoon. Rain will begin as early as 9-10AM for some of our Southwestern Counties and continue to spread Northeast through early afternoon. Southeast Wisconsin may not see rain start until after 12PM.

Steadier rain will be likely for everyone by early afternoon, with hourly rainfall rates near 0.25"/hr at times. A few rumbles of thunder will be possible as well, particularly in Southern portions of the area. While the heaviest rain will exit after 6PM, pockets of light to steady rain will persist into the night.

Temperatures will reach into the low 70s before/as rain starts but drop through the afternoon into the mid-60s as rain picks up in intensity. Winds will also pick up through the afternoon, gusting near 25-30 mph at times from the East.

Rainfall will add up much quicker for some compared to others. South of I-88 will see the highest rainfall totals, with some picking up between 1.0-1.5" or more. Between about I-88 and the IL/WI state line, you can expect between 0.5-1.0" of rain. Far NW Illinois and Southern Wisconsin may only see 0.25-0.5" of rain.

Illinois surpasses 160 tornadoes in 2026

It's been an incredibly active tornado season across the Illinois this year, with more than 160 preliminary tornado reports as of June 18th.

And given recent severe weather events, that number is likely still climbing. That total is 37 higher than all of last year and puts Illinois well ahead of the rest of the country, more than doubling Mississippi, which ranks second with 83 tornadoes. 

From early-season setups to multiple rounds of severe weather, the atmosphere has consistently favored storm development, fueling a prolonged stretch of frequent tornadic activity in recent years. And with the summer months still ahead, Illinois's tornado count will likely climb as we transition into M.C.S (mesoscale convective system) and Derecho season. 

Father’s Day Weekend: Sunshine first, then changes

Shower Chance Late:

Yesterday was about as good as it gets - a perfect 10 out of 10 with sunshine, comfortable temps, and a light westerly breeze. Today doesn't quite match that, but it's still solid - more like an 8.5 out of 10 as we look to stay dry for most of the day. However, a weak system diving in towards the evening will bring an increase in cloud cover and the chance for a few showers, possibly an isolated storm.   

Father's Day Weekend:

Father's Day weekend will have a great start. High pressure settles in Saturday, bringing plenty of sun and comfortable highs in the upper 70s. Sunday for Father's Day itself, looks quiet early on, but clouds will gradually increase as the day goes on, with chances building into the afternoon as a area of low pressure slides to our south. Temperatures will be a bit cooler, holding in the upper 60s.  

Sunday Severe?:

Thunderstorms will be possible, but the better ingredients for severe weather are expected to stay well to our south - roughly in the same areas that were impacted by Wednesday's tornadoes.  
 

Father's Day weekend: Seasonably cool with periodic rain

 This Father's Day weekend will not feature the heat and humidity we typically expect in mid-June, but scattered showers may be possible from time to time. High temperatures may get close to 80 degrees Friday and Saturday, but that is still below the average highs of low 80s that is typical for mid-June. Sunday will be even cooler with widespread rain and clouds.

Friday evening is not rain-free either. A few stray showers may be possible mainly after 6-7PM across the area. While rain will not fall very hard, it may be enough to dampen the ground and the grass where it falls. There is also a very limited chance for a stray rumble of thunder, maybe around 10% during the evening. Be sure to have an umbrella handy if you are outdoors!

While Saturday will be dry, Sunday will bring a much broader chance for shower and a few embedded storms. A large-scale low pressure system will track along Central Illinois, bringing a lot of moisture with it. While we are on the Northern end, widespread showers and even some thunderstorms will be likely starting Sunday morning, lasting through much of the day. All told, a few spots may get upwards of an inch or more of rain between Sunday and Sunday night!

If you have any outdoor plans for Father's Day weekend, Friday afternoon or Saturday will be your best windows for activities. Scattered rain chances will move in by Friday evening and then more widespread rain arrives Sunday. Happy Father's Day!

Severe potential fades across northern Illinois, quieter days ahead

Active Wednesday:

Yesterday's severe weather unfolded a bit differently than it could have, thanks in large part to a morning round of strong thunderstorms. 

This, like last Thursday, helped take the edge off the atmosphere across northern Illinois by overworking the air mass, limiting how unstable things could have become later in the day, ultimately pushing the more significant threat for severe weather to the south. While conditions were less favorable locally for widespread severe storms, the system still managed to produce one tornado in southern Wisconsin. Details on that tornado, including strength and exact path, will be evaluated in the coming day.  

Less Active Days Ahead 

In the wake of that system, we settle into a much quieter and more tranquil stretch of weather heading into the next couple of day. Partly cloudy skies will help make for a pleasant day overall, with a steady breeze out of the northwest keeping afternoon highs in check. Expect us to top out in the low 70s, still a good amount below late-June standards. While most of today stays dry, a weak system sliding in this evening could spark an isolated shower, but coverage remains limited and impacts minimal. 

Friday brings a subtle warm-up as winds shift more westerly, helping temperatures climb back into the upper 70s, much closer to where we should be for this time in June. Along with the warmer air, we'll also have a chance for a few scattered showers and storms during the afternoon. Coverage, like today, doesn't look to be widespread at this point. 
 
 

Old Settlers Days forecast: Isolated rain chances ahead

 Old Settlers Days will not feature the typical heat and humidity we expect from mid-June, but will have periodic chances for rain. Temperatures will range from the upper 60s Sunday to the upper 70s Saturday. There are a few slim chances for rain Thursday and Friday evenings, with higher coverage of rain possible Sunday.

The chances for rain Thursday and Friday evenings will be relatively limited, with only a few stray showers after 6PM each night. Rainfall does not look to come down very heavy, and many spots will be dry at any given time. But if you're heading out, you'll want to make sure you have the umbrella handy!

Better coverage of rain will be possible Sunday with a broader low-pressure system moving through the region. The center of the low will pass South, keeping any strong storm threat mostly downstate, but a few rumbles of thunder will remain possible locally as well. Sunday may not quite be so favorable a day to be outside, so be sure to make your OSD visits by Saturday if you want nice weather!

Wednesday afternoon weather update for northern Illinois

 

6:46pm Update: New: Severe Thunderstorm Warning for northern Green and northwest Rock counties in southern Wisconsin until 7:45pm. Storm is moving east at 45 mph and capable of producing 60 mph wind gusts.

 

5:45pm Update: A TORNADO WATCH has been issued for Green County in southern Wisconsin until 9pm Wednesday evening. Thunderstorms have developed along what meteorologists refer to as the 'triple point'. This is where a low's warm front, cold front, and occluded front come together. Often times this can help enhance the spin in the lower levels of the atmosphere, which is what has happened with the thunderstorms that have moved into southwest Wisconsin.

While the severe threat remains limited for us this evening, we still do have the cold front and low-pressure system to get through this evening. And that may allow for at least an isolated severe storm to impact part of the viewing area through 9pm.

The showers and thunderstorms from this morning have really kept our atmosphere cool and stable. Current temperatures (as of 1pm) are in the mid and upper 50s with a brisk southeast wind. The storm complex from the morning developed a little further south and has pushed the system's warm front down into central and southern Illinois. While there will likely be some shift in the front to the north it'll more than likely remain in central Illinois, and this is where the highest threat for the more significant severe weather looks to remain.

Accordingly, the Storm Prediction Center shifted both the 'enhanced risk' (level 3/5) and 'moderate risk' (level 4/5) southward a bit. Northern Illinois and southern Wisconsin remain within a 'slight risk' (level 2/5) for the rest of the afternoon and evening.

So, what does this all mean for our weather going forward? We'll continue to see a few scattered showers throughout the afternoon as temperatures are likely to creep back into the 60s. There is some clearing taking place over Iowa with the cloud cover and this is slowly starting to allow some instability to build back north into southern Iowa. As the system's cold front and low pressure move east, we will likely see some higher instability develop along the Mississippi River and into parts of northern Illinois through early afternoon. This will keep at least an isolated severe risk going through about 8pm/9pm locally until the cold front passes. The main hazards with any storm that would turn severe would be primarily wind.

Our window for the next round of thunderstorms we'll need to keep an eye on will be from roughly 5pm/6pm through 8pm/9pm.