Isolated thunderstorm chances return this week

 With a calm and relatively cool start to the week, thunderstorms return along with 80-degree heat as we progress through the rest of the week.

With zonal flow and a few low-pressure systems making their way through the Northern United States this week, fronts and enhanced upper-level winds will bring higher rainfall and thunderstorm chances.

After Monday temperatures get back into the 80's as a warm front Tuesday is the start of that. Tuesday in particular will be a day to keep an eye on as currently the Storm Prediction Center has outlined a 1/5 marginal risk for the region.

This outlook mainly highlights the threat for evening thunderstorms along a cold front moving east from Iowa. However, a round of thunderstorms Monday night int Tuesday morning seems likely as well. At this time the bigger focus will be on the later round as there will be the chance for isolated severe potential as instability combined with the eastward moving cold front may initiate storms.

Looking into the rest of the week with passages of fronts through the days and nights shower and thunderstorm potential continues through the week.

Thursday will be on everyone's radar as Independance Day is quickly approaching. During the day on the 4th a warm front will move through the region bringing isolated shower and thunderstorm chances through in the afternoon to early evening hours. Timing on this warm front will need to be forecasted further however it does seem like most precipitation chances along the front seem to move out by 4 p.m. just in time for grilling and fireworks to start! However, trends with this warm front will need to be further monitored, but the night of 4th of July should be very comfortable.

Moving into the rest of the week where thunderstorm chances continue into Friday. Chances Friday are heavily dependent on the movement of the warm front and associated low pressure system together. During Friday morning the trailing cold front with the low-pressure system previously mentioned moves through and with any moisture leftover at least a round of showers and possible thunderstorms seems possible.

Seasonably cool and comfortable through Monday

It was a much warmer day across the Stateline today, as sunshine has really been the big difference with highs in the 80s! This coming despite a cold front and NW winds. Some spots warmed between 10-15° warmer than yesterday.

Cooler and drier air is already settling in across the region, which will allow for overnight lows to drop into the mid-50s under mostly clear skies. It may even be a little chilly, with a cool breeze from the North gusting to 20 mph through Sunday. Sunshine will return tomorrow, but high temperatures will not reflect it nearly as much as today. This time around we only warm into the low-70s.

But the good news is that we will remain dry and sunny for both Sunday and Monday. Moisture begins to filter back in Monday night, bringing our next chances for rain and storms then through Tuesday. Tuesday evening, a cold front will bring a temporary end to precipitation, but that front may lift back through the region sometime Thursday as a warm front, sparking our next thunderstorm chances. While the confidence is low this far out, we may need to start thinking about what 4th of July plans might look like with scattered storms possibly in the forecast.

We have a couple of cool and dry days ahead Sunday and Monday before rain and storm chances return Monday night and Tuesday. Temperatures will run much closer to average as we then play ping-pong with the passing front and associated storm chances through the end of the week. Next weekend looks to return to a dry but slightly cooler state once again.

How this upper-level wind pattern will impact temperatures and precipitation

 With a calm weekend on the horizon and the 4th of July quickly approaching this week we can look at how the upper-level winds will affect the holiday and days after.

With a zonal wind pattern to come this week, it is a great time to explain how a zonal pattern often affects summertime conditions. Zonal flow refers to the upper-level jet stream moving in a flat pattern or only a certain zone of a continent hence the name "zonal" flow. With winds in a straight pattern area under enhanced winds will be a concentrated area for precipitation.

Along with this zonal flow a large high-pressure system will build in the Southern Plains keeping higher temperatures to the south. Along with enhanced upper-level flow this helps keep temperatures in a normal pattern, so a comfortable pattern seems likely.

Looking at precipitation, with average temperatures returning so will average seasonal rainfall with this upper-level jet stream pattern. In the summertime all that is needed for precipitation is moisture and lift, in this case the cause of lift will be these upper-level wind maximums. So, with any moisture return in this pattern will allow for higher precipitation chances.

With the 4th of July ending up in this time frame a comfortable holiday looks likely in terms of temperature however as trends get closer precipitation may be likely on the holiday. However, follow along with future forecast here on my state line.

Rain chances return to conclude the work week, low severe risk

Mother nature gave us and our air conditioners a well-deserved break from the heat Thursday. Clouds slowly increased throughout the day, leaving highs for most locales in the upper 70s.

Highs remain in the upper 70s, close to the 80-degree mark this afternoon. However, it comes with less sun and a better shot at some rainfall as our next storm system glides across the Midwest. 

Whether your daily routine takes you out the door this morning or this afternoon, make sure to have the umbrella on hand. Forecast models show scattered showers remaining a possibility for a good chunk of the day, with chances lingering into the early stages of Saturday. A few thunderstorms will be possible, especially this evening into early Saturday as a cold front approaches from the west. 

 

One or two of these could become strong to severe, posing the risk for damaging winds, small hail, and flash flooding. It's for this reason that the Storm Prediction Center has placed all of northern Illinois and southern Wisconsin under a level 1 marginal risk for Friday night/Saturday morning.

 

Conditions rapidly dry out following Saturday's cold front, resulting in a partly cloudy afternoon sky. There will still be enough of a westerly wind present for highs to peak in the mid 80s. It won't be until Sunday where the full effects of this frontal passage will be felt as highs only peak in the mid 70s.

 

Rain and thunder chances return Friday

 

High temperatures Thursday afternoon warmed into the mid and upper 70s with Rockford's high reaching 78 degrees. This was the 'coolest' high temperature since June 11th when the mercury reached 79. The next day we warmed into the low 90s!

High pressure moving through the Great Lakes Thursday afternoon kept skies mostly sunny, but throughout the evening you'll notice a gradual increase in cloud cover. The clouds are the result of our next storm system that'll move through northern Illinois and southern Wisconsin Friday. An increase in both warm air and moisture throughout the day will work to overcome the dry air left behind from Thursday's high-pressure system. Overtime, this will lead to an increase in scattered showers Friday morning and afternoon.

Rain showers remain scattered Friday but as a cold front nears late Friday night, a few scattered thunderstorms will be possible. There is a low risk for an isolated strong storm or two during that time with the potential for strong wind gusts through Saturday morning. 

Because of that the Storm Prediction Center has placed all of northern Illinois and southern Wisconsin under a 'marginal risk' for Friday night/Saturday morning.

The cold front will sweep through the region during the morning Saturday, with a few storms possible along the front later in the afternoon. The highest risk for that, however, will be further to our southeast. High pressure moves back in Saturday evening leaving skies dry heading into Sunday.  

Beautiful weather settles in ahead of Friday's chance for rain

If you were a fan of Wednesday's weather, then you're really going to love the forecast for today. Today is when the full effects of Tuesday's frontal passage is set to arrive, resulting in comfortable temperatures and lower humidity. In fact, we're likely going to see our coolest day since June 11th.

Temperatures this morning are sitting 10°-15° cooler compared to Wednesday morning, with most waking up in the upper 50s. The cooler start to our day will pave the way for a cooler afternoon as temperatures struggle to climb out of the 70s. 

It's also important to note that dew points later on will be sitting very comfortably in the low 50s. This will occur under sun-filled skies to start, with fair-weather cumulus clouds popping up for the afternoon. All in all, a perfect day for outdoor plans and for those who plan to attend "Dinner on the Dock" at the Prairie Street Brewhouse this evening.    

Clouds increase overnight, leaving temperatures slightly warmer come Friday morning. This is all in response to an area of low-pressure that zips across the midsection of the lower 48. 

With tomorrow's cloud cover does come the chance for showers and a few isolated thunderstorms. I will say, forecast models have really backed off the idea of tomorrow featuring heavy rain potential. 

Which, considering how much rain we have seen over the past week or so I'm okay with. But I would still think a few heavy downpours will be possible, especially if we do see a few storms develop. With that being said, the best chances will arrive during the afternoon and evening, with chances lingering into the first half of Saturday. The Storm Prediction Center continues to keep the entire region under a level 1 of 5 Marginal Risk for severe weather, with damaging winds being the main concern. 

Another cold front is scheduled to pass though over the weekend, resulting in another cool down. Highs peak in the low 80s Saturday before cooling back into the low 70s Sunday. 70s continue into next week, with 80s making a return by Tuesday.

Taking a look into Early July

 With the official start of summer passing just a few days ago, June is quickly coming to an end as well. With June closing out we can begin to look into the pattern moving in for early July as well as an early Fourth of July forecast.

Taking a look at temperatures first, a large ridge begins to form over the Southeast and Southern Plains creating a heat dome over the southern United States. However up the north we move out of the 90 degree heat we have been experiencing as more average temperatures begin to move into the Midwest with upper 70's and low 80's dominating the region.

This will offer a much more comfortable pattern as with lower temperatures comes lower dewpoint temperatures as well being in the mid to upper 60's. Temperatures and dewpoint temperatures ultimately impact humidity so with lower temperatures as well as dewpoints humidity won't be as heavy as they have been.

In terms of precipitation, we will continue to receive rain and just above average rainfall for this time of year. With the previously mentioned ridge, upper-level winds will return to the Midwest and helping aid in precipitation chances.

After experiencing a dry spell, the past month much needed rainfall will continue so shower and thunderstorm chances will begin to increase. In terms of national precipitation, the Southeast will be experiencing not only high heat but drier conditions. While out west the monsoon and heavy rain season will begin in the desert Southwest.

With the Fourth of July falling in this period an early forecast can start to be made for the holiday. A very comfortable holiday is seeming increasingly likely as we approach the fourth with upper 70's being most likely. With little to no wind as well as clouds clearing by night, the firework forecast seems to be almost perfect for viewing fireworks throughout the night.

Cooler, more enjoyable air filters in behind recent cold front

Forecast-wise, there's plenty to be happy about. One, after being placed under three severe thunderstorm watches over a 24 hour period, severe potential steers away from the region the next few days. And two, our most recent frontal passage spells cooler and less humid times moving forward.

Those changes however haven't fully settled in just yet as the cloud cover in place this morning will make for another warm start to the day.

By this afternoon, skies will turn partly cloudy, humidity levels drop, and high temperatures will trend cooler in the low 80s. High pressure sliding into the western Great Lakes will make for a mostly clear night, with temperatures ending up seasonably cool in the upper 50s by daybreak. These changes will really make their presence known Thursday as the air will feel much more comfortable. Highs take a step back as well, landing in the upper 70s.

Moisture pooling in behind a warm front will bring the likelihood for a soggy end to the work week. Of course, with Friday's wet forecast comes the potential for a few strong to severe storms. 

Right now, the Storm Prediction Center has the entire region under a level 1 Marginal Risk, with a slightly higher threat focused to our southwest. Chances will then linger into the early stages of Saturday as the associated cold front slides through.   

Tuesday severe weather update

 After a very active start to the day severe thunderstorm activity is beginning to wane as the morning moves through. Numerous severe thunderstorms warnings have been issued through the early morning however a possible second round is still in place for later today.

Currently much of the region is still under a severe thunderstorm watch however the Storm Prediction Center and local national weather service offices are beginning to cancel this watch as the storm complex moves east. 

Taking a look at the radar all thunderstorms are moving east and out of the area through the rest of the morning. With any continued storms this morning they will run the risks for mainly heavy downpours and intense lightning however some small hail is still possible.

Throughout this afternoon the sun will return behind these storms bringing hot and humid conditions. The Storm Prediction Center still does have a marginal risk for much of the reason for an expected second line to develop this evening. However, as of now most thunderstorm activity begins to move east and begins to slowly weaken. But as we move through into the afternoon, flooding may become a risk as areas have already experienced over an inch of rainfall through this morning with more possibly to come later.

Multiple rounds of storms possible Tuesday, some severe

Severe thunderstorm watches are in place to our north and northeast as a potent Mesoscale Convective System (M.C.S) slides into eastern Wisconsin and Lake Michigan. While the Stateline missed out on the brunt of this line, storms are back-building off it's backside across southwest Wisconsin. Currently, these are non-severe, though are producing 40 mph winds and nickel size hail as they slowly push east towards Green, Rock, and Walworth County. Storm chances with the first round will remain possible into the mid to late morning hours.

A secondary round looks possible late this afternoon into the evening as our next cold front slides in from the north and northwest. 

As of this morning, the Storm Prediction Center has areas between Janesville and Rochelle under a level 1 Marginal Risk while leaving areas south of Rochelle under a level 2 Slight Risk. High CAPE, modest shear, and high moisture will allow additional storms and clusters to develop, posing a risk for damaging winds and heavy downpours. 

A few showers and thunderstorms will remain possible into the early stages of tonight. However, conditions dry out and become less humid as high pressure settles in behind today's cold front. Partly sunny skies will be in place both Wednesday and Thursday, with highs peaking in the low 80s. Rain and storm chances quickly return Friday, which will help cool highs back into the 70s.

 

 

 

 
 

Late Monday evening weather update

 

The severe thunderstorm watch that had been issued for southern Wisconsin and most of northern Illinois earlier Monday evening has been canceled. However, isolated thunderstorms will continue throughout the late evening. The greatest threats with any of these storms will be heavy rainfall and hail. A Flash Flood Warning has been issued for southeast DeKalb County until 3:45am.

Our focus continues to remain on the storms that are developing in northern Wisconsin late Monday night, and their progress to the east and southeast. The latest set of computer guidance has these storms strengthening into a storm complex but moving more east than southeast overnight.

If this occurs the track of the storms would move more into central and east-central Wisconsin, from Green Bay to Milwaukee before moving out over Lake Michigan early Tuesday. This would place the strongest and most damaging wind threat to the north.

Storms may then develop to the west and southwest over northern Illinois around sunrise, still holding on to an isolated wind threat through early morning.

The line of storms would likely move out between 8am and 10am with heat and humidity quick to build in behind. As warm air continues to spread east across the area dew point temperatures are expected to warm into the 70s. This would cause humidity values to increase quite a bit, potentially pushing the heat index close to 100 degrees during the afternoon.

A cold front coming in from the north during the evening would then become the focus for additional thunderstorms after 6pm. The exact placement of those storms would depend on where any outflow boundaries from the early morning storms set up, and where the atmosphere has been able to recharge. This could end up being focused more across northwest Illinois and Iowa, quickly shifting south through west-central Illinois and northern Missouri after sunset.

We'll continue to monitor the storms through the night and into Tuesday morning. Be sure to check back with the forecast during the morning.

 

Timing of severe thunderstorms tomorrow early morning

 Overnight tonight into the early morning hours of tomorrow will be a time to be weather ready and pay attention to alerts as an overnight severe thunderstorm threat looks to impact the region.

Currently the storm prediction center has both an enhanced and slight risk out for the entire region. Within these risks damaging wind gusts will be the primary threat through the early morning however hail and a isolated tornado cannot be ruled out.

Thunderstorm development is currently ongoing in Minnesota and Wisconsin, these thunderstorms will continue to grow and redevelop throughout the evening and will push southeastward through the night. These thunderstorms will be following the axis of instability as this instability will be the fuel for the thunderstorms to persist overnight. By 10 p.m. a line of strong to severe thunderstorms is expected to develop and is forecasted to move southeast into the state line region.

Through the early morning hours tomorrow a large complex known as an MCS (Mesoscale Convective System) is expected to develop and intensify in Wisconsin. The track of these thunderstorms will be determined by the instability that is in place and the "swath" of instability these storms will follow. In the case of an instability axis positioned as shown, this would be an outcome where severe thunderstorms would impact the region.

Timing currently is the hardest part of the forecast as it all depends on how storms progress through Minnesota and Wisconsin. However, with current trends the line of thunderstorms is forecasted to reach the region from 3-5 a.m. bringing severe chances with it. With an instability axis positioned further south further development will be expected creating a flooding risk as well.

By the time the sun is up from 6-7 p.m. thunderstorms are forecasted to be out of the region. Depending on how these storms evolve through the morning hours tomorrow this will then determine the next round of storms that may develop into tomorrow afternoon.

However, the focus is on the early morning hours of Tuesday with the enhanced (level 3/5) risk. Although this is overnight, it will be crucial to have severe weather safety plans in place and make sure your phone volume is on so warnings can be properly heard through the night.

 

 

Storm chances quickly ramp back up following a beautiful Monday

Surveys conducted Sunday by the National Weather Service confirmed 5 tornadoes across southern Wisconsin, including the EF-2 tornado that struck the south side of Janesville. 

Additional information is expected to come about today as surveys continue. Stay tune! 

 

Fortunately, the work week kicks off on a quiet note as high pressure moves overhead. Expect partly sunny skies with highs in the upper 80s. Humidity won't be too much of an issue as dew points this afternoon look to sit in the upper 50s. 

Overnight, our attention will then shift to what occurs to our northwest this evening. An impulse sliding into the state of Minnesota will help spark up a strong line of showers and storms, one of which will take aim at the Stateline early Tuesday morning. 

As of this morning, lots of uncertainties remain including the strength of said M.C.S and where it will eventually end up. In fact, forecast models show a couple of scenarios playing out.

Scenario #1, storms roll through the area early, posing a risk for damaging winds and heavy downpours. This would push the better atmospheric parameters south of the region, resulting in no evening threat. 

Scenario #2, there's enough time between the early-day round and the evening round for the atmosphere to significantly recover. This would increase our chance for severe storms Tuesday evening, with all hazards being on the table. 

Scenario #3, storms back build off the the morning M.C.S and sit over N. Illinois for a good chunk of the morning hours. This would also play a role in limiting the afternoon and evening threat. All in all, monitor the forecast and make sure you have multiple ways to get watches and warnings. 

The Storm Prediction Center has the Stateline under a level 2 of 5 Slight Risk for tonight and Tuesday. Again, the Slight Risk for Tuesday may change as more details come about. The cold front responsible for Tuesday's severe threat will also be responsible for the cooler and quieter times that follow. Wednesday and Thursday feature party sunny skies, lower humidity, and highs on either side of the 80-degree mark. Friday would be the next day to monitor for storm potential.

Heavy rainfall and flooding continue early this week

 After last night's round of severe thunderstorms heavy rainfall has sparked multiple flood warnings and flood watches throughout the state line. Widespread heavy rainfall stuck around for much of the night with training storms or continuously developing storms causing heavy rain to fall on areas for over an hour.

Many areas over the state line received widespread 2–3-inch rainfall which for many in the farming community was well needed. Areas in purple on the map above received 3-4 inches and even more with some areas in McHenry County reaching almost 5-inch rainfall totals.

Currently multiple flood warnings are in effect over multiple counties lasting until 10:15 pm as well as portions of the Rock River in Southern Wisconsin. As well multiple flood watches are in effect in the darker green, these watches last through the next couple days into Tuesday as more rainfall will be expected during the day and evening Tuesday. With this next threat of heavy rain Tuesday more flood warnings may be warranted as combined with the current rainfall totals can cause some enhanced flooding issues.

Taking a look at rainfall chances these next few days both overnight and especially all of Tuesday will be a time to keep an eye out for more rain. Monday overnight a line of showers makes its way through the region however Tuesday again brings the chance of strong to severe thunderstorms, with those very heavy rainfall as well. With multiple rounds of showers and thunderstorms through most of the day, rainfall totals can rise over an inch or more bringing more flooding threats.

With the threat of more heavy rain to come it's important to review some flood safety tips as with heavy downpours water can rise quickly. If a flash flood or flood warning is issued, make sure to get to higher ground and follow the "Turn around don't drown" phrase. Never drive on a flooded roadway as water can be visually deceiving. In most cases only one foot of water is needed to make cars float away, with heavy downpours and strong winds from thunderstorms downing leaves and branches this leads to an enhanced risk of sewers flooding and roadways becoming impassable.

Pay attention to both watches and warnings as water can rise quickly especially in flood prone areas near waterways and lower areas.