Very isolated showers Monday evening

 

Skies have remained partly cloudy Monday as temperatures warmed into the low 80s. While most will remain dry through the evening, a few very isolated showers have developed over a portion of northwest Illinois. These are slowly drifting to the southeast. We may see a few more isolated showers develop south of Highway 20 through sunset, but any precipitation that does develop will come to an end after dark. Under mostly clear to partly cloudy skies tonight temperatures will dip into the low 60s.

Our weather pattern remains somewhat unsettled this week, but it doesn't mean that the week will be a washout. With winds in the jet stream moving from northwest to southeast, it'll allow numerous weak upper-level disturbances to move through. Each one, passing through every 12-24 hours, will bring with it a small chance for a few showers and thunderstorms.

Right now, the main storm track has been positioned to the west and southwest of the Stateline. By Tuesday night, a warm front will lift closer to northern Illinois. As it does, moisture increases bringing a chance for a few showers and isolated thunderstorms Tuesday night/Wednesday morning. The next chance will be again Thursday night, Friday, and then into the weekend as the overall pattern begins to break down. During that time temperatures will remain in the low to mid 80s, warming into the upper 80s Thursday and Friday. Humidity will also be on the increase.

A brief break in the high heat and humidity

 

Temperatures Sunday afternoon warmed into the upper 70s and low 80s with Rockford reaching 81 degrees. It was still warm - after all it is July - but it felt much more comfortable when compared to the last few days.

Other than a few clouds moving through during the evening, skies should remain mostly clear overnight. Temperatures are expected to fall into the upper 50s and low 60s for the start of Monday. Monday will be almost a carbon copy of Sunday, just with a little less cloud cover, lighter winds, and slightly warmer temperatures. The forecast high for Monday is 84 degrees - which is right where we should be for the end of July.

Under northwest flow in the jet stream - meaning winds move in from the northwest - the high heat and humidity will remain focused over the southern Plains. The strong ridge of high pressure that has been persistent over the last month or so will shift some. This will allow for a break in the excessive heat that has been plaguing parts of the Southwest, but unfortunately not for those who are in the southern Plains or South.

For us, temperatures will remain closer to average - with highs in the low to mid 80s - but we will see those numbers climb by the middle to end of the week. A warm front will lift across central Illinois and be the focal point for a few showers and thunderstorms downstate during the day Wednesday. As that boundary lifts north, so will the moisture. This could bring us a few showers and thunderstorms late in the day Wednesday and Wednesday night. Following Wednesday the next chance for rain looks to occur Friday.   

Heat Advisory remains in effect, severe storms possible again this evening

Hot & Stormy Friday:

Storms that prompted multiple severe thunderstorm warnings earlier are currently in the process of moving out of the area. Mainly warned for 60 mph straight-line winds, with all of the warnings remaining south of highway 20. 

With this morning's round coming to an end, our focus will turn back to the excessive heat that sticks around for our Friday. Clouds this morning should give way to more sunshine by mid to late morning, allowing temperatures to soar into the low 90s for the third straight day. 

McHenry, Boone, Winnebago, Jo-Daviess, Carroll, Stephenson, Ogle, and Dekalb counties in northern Illinois, as well as Green, Rock, and Walworth counties in southern Wisconsin remain under a HEAT ADVISORY until 9PM. 

The remaining two counties, Lee and Whiteside, will remain under the EXCESSIVE HEAT WARNING until 9PM as well. Areas under the heat advisory could see heat index values approach or even eclipse the 100-degree mark. Those to our south that are under the excessive heat warning could see even higher values, closer to 110°. Again, if you plan to be outdoors, remember to implement heat safety. You can beat the excessive heat by wearing light colored clothing, taking frequent breaks in the shade, and of course remaining hydrated. 

Second Round of Storms:

This afternoon's heat and humidity will help prime the atmosphere for another round of severe storms starting late this afternoon. Overnight, the Storm Prediction Center upgraded our region to a level 3 enhanced risk for severe weather. 

Biggest concern between 4PM and midnight will be damaging winds, large hail, and heavy rainfall. Post frontal passage, cooler and less humid air will slowly filter in. Saturday will still be warm with highs in the upper 80s. By Sunday, highs will peak near-average in the low 80s. Want more good news? High pressure builds in behind the departing cold front, resulting in a more sun-filled forecast and a less active one.

Excessive heat warning issued for some

Extreme Heat Continues:

For a majority of the summer, mother nature has been extremely kind to us by keeping the temperature and humidity departments under control. However, it was only a matter of time before she threw a little more heat and humidity our way. Despite having severe thunderstorms and cloud cover all morning long, highs for a few peaked in the low 90s.

Heat Advisory:

This was only the beginning as the extreme heat will continue to be the big headline as we round out the work week. So much so that the National Weather Service expanded the heat alerts to now include the entire region. McHenry, Boone, Winnebago, Stephenson, Jo-Daviess, Carroll, Ogle, and Dekalb counties will be under a HEAT ADVISORY until 9PM Friday. The remaining two counties, Lee and Whiteside, will be under a EXCESSIVE HEAT WARNING until 9PM Friday as well. 

With bright sunshine and a light southeasterly wind on tap for the Stateline, high temperatures today look to peak in the low to mid 90s. Areas under the heat advisory could see heat index values approach or even eclipse the 100-degree mark. 

Those to our south that are under the excessive heat warning could see even higher values, closer to 110°. Friday will be just as warm and just as humid, with highs peaking in the mid to upper 90s. Again, if you plan to be out during the afternoon and evening hours, remember to implement heat safety. You can beat the excessive heat by wearing light colored clothing, taking frequent breaks in the shade, and of course remaining hydrated. 

Storms Still Possible:

The thunderstorm threat today will be highest across portions of Minnesota and Wisconsin. But in a similar fashion to Wednesday morning, we'll have to keep an eye on where these storms track overnight. Guidance does bring a slight chance for a few isolated storms late Thursday night into Friday morning. Overall, the severe threat is low. But if any storm were to remain severe as it track into the region, damaging straight-line winds will be the biggest concern. 

The severe threat ramps up a bit for Friday afternoon into Friday night as a low pressure system and it's associate cold front slide in from the northwest. The Storm Prediction Center has kept the entire area under a level 2 slight risk, with winds and hail again being the biggest concern. 

Post cold front, highs will cool back into the low to mid 80s for the weekend. Along with the cooler weather comes more sunshine as high pressure builds over the Great Lakes. 

Few storms early, good portion of Illinois placed under heat advisory

Morning Storms?:

All eyes this Wednesday morning are on the cluster of showers and sub-severe thunderstorms that are tracking into western Wisconsin. The million dollar question is if they hold together and if so, how much of this cluster propagates south towards the region. Scenario #1 involves this cluster completely missing the Stateline area, with activity along the tailing cold front tracking through before lunchtime.

Scenario #2 involves this thunderstorm complex maintaining its strength, moving east-southeast towards the WI/IL border as it follows a pool of rich moisture and instability. Should this scenario occur, our severe threat would slightly increase, with damaging winds being the biggest concern. Right now, I'm leaning towards scenario #1. 

With that being said, the Storm Prediction Center left areas east of Monroe, Freeport, Forreston, Dixon, and Amboy under a level 1 Marginal Risk. Thunderstorm potential would then drop, leaving skies partly cloudy for the afternoon and evening. Smoke was the big issue with yesterday's warm-up, leaving highs in the upper 80s. However, with less smoke in our atmosphere, and with a west-southwest wind in place, temperatures should warm into the low 90s. Skies will continue to clear overnight, with temperatures falling into the upper 60s come sunrise Thursday. 

Hottest Stretch Ahead:

Heat Advisories stretch from northern Texas into the Ohio Valley and Great Lakes. So far, Whiteside County is the only county in our forecast area that has been placed under a Heat Advisory. 

But I'm sure as Thursday approaches, the National Weather Service will consider putting more of our region under this advisory.  

Thursday is to become the hottest day of the year as temperatures aim for the upper 90s. What will make matters worse is the climb in humidity levels, which would place heat indices near or above 100°.  

More of the same is expected for Friday.  If you plan to attend the Stephenson County Fair, the Lee County Fair, or plan to be outside in general, please implement heat safety. Drink plenty of water, and take frequent breaks in the shade. A cold front Friday will not only bring another chance for thunderstorms, but also relief from this week's heat and humidity. Highs fall into the mid 80s Saturday, then low 80s for Sunday and Monday. High pressure builds behind the front, resulting in a drier weekend.

Wildfire smoke slowly exits, 90° stretch begins today

Leftover Smoke:

Wildfire smoke lingering around the Stateline continues to make the air quality unhealthy for some. For that, the EPA continues to keep areas to the north and east of Rockford under an Air Quality Alert until midnight tonight. Young children, the elderly, and those who have lung/heart issues should limit time outdoors, especially during the morning hours.   

Hot Tuesday:

It seems that this plume of smoke will slowly filter out as we head into the afternoon. In doing so, leaving us with wall to wall sunshine. That, along with a light wind out of the south will allow temperatures to soar into the low 90s for the 6th time this year. 

Thankfully, humidity won’t be too terrible as dew points aim to sit in the low 60s this afternoon. Most of the night will be dry under a partly cloudy sky, with temperatures falling near the 70° mark. However, we'll have to keep an eye on the thunderstorm activity that develops to our northwest this evening. The strength of that activity as it approaches the region will be the determining factor into our Wednesday's forecast pans out both heat-wise and thunderstorm-wise. 

Hot, Stormy Wednesday?:

When it comes to Wednesday's forecast, here's the two scenarios that could happen...

1. Thunderstorms remain strong, pushing through the region between 4AM-9AM. The wind shift that accompanies the early-morning activity would allow highs to climb into the upper 80s/low 90s. The best chance for redevelopment would be to our east, in areas around Chicago and Lake Michigan.

2. Thunderstorms weaken on approach, leaving us with plenty of sunshine and a warm wind out of the south and southwest. This would make highs in the mid 90s a decent bet. Humidity would also spike as dew points would be sitting above 65°. Again, we'll have to see how these thunderstorms behave once they form and once they begin to approach the region.

For right now, the Storm Prediction Center continues to leave the entire region under a level 2 slight risk, with a level 3 enhanced risk placed over S. Michigan, NE. Indiana, and NW. Ohio. Large hail, damaging winds, and a brief tornado would be the biggest concerns if thunderstorms remain strong. 

Thursday looks to be the hottest day of this stretch with highs peaking in the upper 90s. The risk for thunderstorms is lower, meaning there won't be much to interrupt Thursday's warm-up. With dew points reaching the low 70s, expect heat indices to climb or even eclipse the 100° mark. Again, if planning to be out and about, heat safety will need to become a huge priority for not only you, but your family, and even your pets. Highs for the fourth straight day will reach the 90s before a cold front slides in early Saturday, leaving us in the 80s Saturday and Sunday.

Smokey skies return to the Stateline

 

Smoke-filled skies return once again to the Stateline Monday afternoon from the ongoing wildfires in Canada. Sinking air has brought the smoke aloft, down near the surface reducing visibility for many.

Hazy skies and reduced visibility will continue through Tuesday morning, but with the jet stream shifting some into Tuesday night the hazy skies should begin to improve. Air quality alerts are in effect until Noon Tuesday for southern Wisconsin and will begin at Midnight, lasting through Tuesday night, for McHenry County.

Improvements in both air quality and visibility will take place as the thicker smokes shifts east and southeast Tuesday afternoon and evening. But it's likely, though, that we continue with the hazy conditions through the week.

Summer's hottest stretch arrives this week, severe potential Wednesday

Heat Cranks Up:

The rather pleasant weather we endured all of last week stuck around for the weekend. Highs both Saturday and Sunday fell on either side of the average mark for late July (84°).   

Significant changes lie just around the corner as the extreme heat over the western U.S spills into the Midwest, allowing temperatures locally to become noticeably warmer. Starting with today, temperatures will surge into the upper 80s. Suns-filled skies early on will give way to a few cumulus clouds this afternoon as a lake-enhanced boundary pushes inland. This may bring the slimmest chance for an isolated t-storm or two to areas east of I-39. 

Conditions remain fairly quiet under a partly cloudy sky overnight, with temperatures falling into the mid 60s come sunrise Tuesday. 

It's during this time in which we see our winds take a turn from the northwest to the south, commencing the climb in temperatures. Under partial sunshine, highs Tuesday return to the low 90s. 

Now, when it comes to this week's extreme heat, there are two components we'll have to keep an eye on...

1. How far east does the heat travel?

2. Does storm chances interfere?

As of this morning, it seems that storm chances will not interfere with Tuesday's warm up. But that can't be said about Wednesday.

Some Severe Wednesday?

Earlier this morning, the Storm Prediction Center placed the entire viewing area under a level 2 slight risk. It seems guidance is showcasing the potential for redevelopment along a nearby outflow boundary Wednesday afternoon/evening. 

If this scenario does pan out, large hail and strong winds are to be the biggest concerns. And depending on the overall coverage of these thunderstorms, Wednesday's warm up could be in jeopardy. This forecast is subject to change over the next 24 to 36 hours. But as of this moment in time, highs for the second straight day are expected to peak in the low 90s. Thursday continues to feature the warmest air with this upcoming hot stretch, with highs landing in the mid to possibly upper 90s. 

This is a stretch of hot weather that the Stateline hasn't seen since June of last year. Now, not only will temperatures be ramping up, but humidity-levels will become more of a factor by the day. 

Come Thursday and Friday, it’s likely that we'll see heat index values sit near or eclipse 100° at times. If planning to be out and about, heat safety will need to become a huge priority for not only you, but your family, and even your pets. 

Another chance for storms Sunday before the heat is on next week

It was another warm and near normal day in the Stateline for temperatures. Scattered thunderstorms developed mainly East of I-39 during the afternoon and evening, helping to cool some areas down a bit quicker before 7PM. A second wave of storms will swing through the area between 9PM and Midnight Saturday night. This round will be a bit more widespread than the storms from this afternoon, with a few holding the potential for gusty winds and small hail, along with the heavy rain and frequent lightning.

Tomorrow will bring another warm day with highs in the mid-80s and additional spotty storm chances. These will be very isolated, so most will likely stay dry through the afternoon. But similar to Saturday, even quick downpours may ruin outdoor plans quickly, so keep an eye to the sky!

Then we turn our eyes toward next week, where we will see some much warmer weather. The heat dome currently impacting the Southwestern U.S. is being held in place by the jet steam at the moment. But the jet stream will lift North, allowing for that heat dome to move East into the middle of the week. Mid and upper-level temperatures will support afternoon highs well into the 90s for some days.

As the large ridge of high pressure associated with the heat dome inches closer, it will also bring Northerly flow in the upper levels to us locally. This will provide the steering for potential storm systems along the outer edge of the high pressure. We may see a few chances for rain even during the middle of the week. The caveat is that if we see more rain on any given day, that will put a limit on how much our temperatures will warm on that day. Counter to that, if we see no rain, we could see some steamy afternoons. There is still plenty of uncertainty, but it is best to be prepared for both scenarios this week.

Even with the rain considerations, our forecast high temperatures still reach into the 90s for the middle of the week. Especially with Wednesday and Thursday, we could see heat index values reach into the triple digits at times. This is because of the persistent flow at the surface helping to bring moisture from the South and the very warm air mass helping to warm us up.

Highs remain near normal for Sunday before starting the climb into the upper 80s and 90s into the week ahead. We have a persistent chance for rain most of the days ahead but will likely need to keep an eye on how each day progresses going forward. 

Comfortable Friday ahead, multiple 90-degree days next week

Comfortable Friday:

Mother nature is the REAL MVP, mainly because she brought us spectacular weather this week. Rockford's highs the last 5 days have been either at or below the average mark for late-July. Humidity levels were at their worst Thursday morning as we awaited the passage of our next cold front. But now with the cold front to our east, Friday's forecast looks to be every bit as nice as the last 5-day stretch! 

Skies will be sun-filled at first, with sunshine mixing with a few clouds during the afternoon. With winds lightly blowing out of the north and northeast, highs will roll back a few degrees, landing in the low 80s. That, along with comfortable humidity will make this afternoon perfect for outdoor activities. Conditions remain quiet overnight under partly cloudy skies, with temperatures falling back near the 60° mark. 

 

Weekend Outlook:

A vast majority of Saturday and Sunday will be dry. However, with a few weak upper-level disturbances passing over Illinois, a few widely-scattered showers or thunderstorms cannot be ruled out. Keyword being scattered, meaning not everyone is going to get in on a chance for rain this weekend. Highs will still end up near or just above average. Humidity-levels will be comfortable to start, but should increase slightly towards the end of the weekend.

Next Week's Heat:

Our attention then turns to the arrival of possibly the hottest air of the summer next week. Forecast models continue to show the expansive heat dome out west expanding into the Midwest. This is the same heat dome that has brought high temperatures in multiple spots in the southwestern and western portions of the U.S at or above 110°. Thankfully, we are NOT talking about temperatures getting that extremely hot. But enough hot air will push our way to allow temperatures to peak near 90° on Monday, and then low 90s for Tuesday, Wednesday, and into Thursday. Tagging along with the heat will be a rise in humidity, which may allow heat index values to approach or even exceed the 100° mark during this stretch.

Seasonable into the weekend, heat cranks up next week

Thursday's Cold Front:

Wednesday marked the third day in a row where N. Illinois and S. Wisconsin enjoyed nothing but beautiful sunshine, seasonably warm temperatures, and somewhat comfortable humidity. 

Thursday begins with a small chance for an isolated shower or thunderstorm thanks to a cold front dropping in from the northwest. Thankfully, severe weather will not be a concern. Once the frontal passage is complete, winds will quickly shift to the northwest, allowing mixed sunshine to return and humidity levels to drop. Temperatures won't be impacted by the wind shift, with most of our local airports peaking in the low 80s. Winds should slowly subside overnight, with temperatures falling back into the upper 50s by Friday morning. 

Pleasant Friday:

Friday in my opinion looks is the pick of the 7-day as sunshine is featured from start to finish. Not only that, we'll have seasonable temperatures in place along with extremely comfortable humidity. A vast majority of Saturday and Sunday will be dry. However, with weak waves passing over Illinois, an isolated shower or thunderstorm cannot be ruled out. Highs will still end up near seasonable-levels.

Heat Cranks Up:

The bigger headline as we jump into next week is the rise in our temperatures. Ridging over the western U.S looks to slide eastward, allowing some of the heat underneath it to spread into the Midwest. Forecast highs are expected to climb back into the upper 80s Monday afternoon, with low 90s possibly returning both Tuesday and Wednesday. 

Now, Rockford has only recorded 5 90-degree days this year, which is much lower than what we had at this point last year (15). And typically between the May to July time frame, we average 9.7 days with temperatures at or above 90-degrees. But with the heat that is on the way, we may be able to add a few more before we make the jump into August.

Dry for Wednesday, few storms possible overnight

Dry Wednesday:

Mother nature cooked up another beautiful mid-summer day across the area Tuesday. Skies were less smoke-filled, with temperatures climbing into the upper 70s and low 80s. Highs today will be a few degrees warmer, thanks to not only more sunshine but also today's south-southeast wind. 

Storms Possible Overnight:

Further to our northwest, a scattered round of thunderstorms will develop along a cold front this afternoon and evening. Forecast models bring what's left of this activity into the Stateline during the early stages of Thursday. Overall, the coverage remains isolated, and the severe risk is low. However, a strong to severe storm cannot be ruled out, with hail and gusty winds being the biggest concerns.

Drying Back Out:

Thursday starts off on a muggy note. But once the cold front is through, winds will quickly shift to the northwest, allowing sunshine to return and humidity levels to drop. Despite the cooler wind, highs will still manage to peak in the mid 80s. We round out the work week on a pleasant note, with Friday featuring plenty of sun and highs in the low 80s.

Isolated showers/storms move in Wednesday night

 

It was another beautiful summer afternoon with temperatures warming into the upper 70s and low 80s under partly cloudy skies. Clouds will clear out once again Tuesday evening, leaving mostly clear skies overnight. Temperatures will dip back into the 50s before reaching the mid 80s Wednesday afternoon.

Skies will remain dry through most of the Wednesday, but showers and isolated thunderstorms are set to return late Wednesday evening. A cold front moving through the Plains and Midwest Wednesday will sink closer to southern Wisconsin and northern Illinois Wednesday night. As it does, a few showers and thunderstorms will be possible. Coverage, however, is expected to remain isolated.

The risk for severe weather remains to the northwest Wednesday, and then shifts into Indiana Thursday as the cold front passes. With a slight rise in instability Wednesday night, there may be a storm or two that grows enough in strength to produce some stronger winds, but our overall severe threat remains low.

Rain showers move out Thursday afternoon with highs warming back into the mid 80s. Temperatures will remain in the low to mid 80s through the

weekend, warming back into the upper 80s going into next week. 

Heat and humidity set to return next week

 

Temperatures remain very comfortable these next few days with highs warming into the upper 70s and low 80s during the first half of the week, then low to mid 80s by the end of the week. Dew points won't climb much with high pressure over the Great Lakes. This will keep comfortable levels of humidity around locally as moisture continues to rise to the south and west. Eventually, that moisture will move in our direction bringing both the return of heat and humidity next week.

A strong ridge of high pressure over the Southwest has brought record setting heat for residents from California to Texas. While the heat remains out west this week, the ridge will eventually begin to break down bringing more of the heat and humidity further east.

This looks to begin as soon as next Monday with highs reaching the upper 80s, possibly low to mid 90s. But that will depend on any storm chances that may develop. Longer range outlooks highlight the higher probability for temperatures reaching above average (average high is the low 80s) the last week of July.

As for precipitation, it looks like we may settle into a drier pattern with a higher probability for below average precipitation across the Plains, Midwest, and Northwest.