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!