Heaviest Rainfall Shifts East as Gusty Winds Continue

The rain has been steady for some across Stateline, adding up to an additional half an inch to three quarters inch Wednesday evening. This has pushed the two day rainfall totals so far (Tuesday & Wednesday) to over two inches in some locations.

The rain will be coming to an end for most Wednesday night, but continue for areas in northeast Illinois through Thursday morning. A deepening low pressure system moving east of

the Great Lakes will continue to pull further east during the day Thursday, taking most of the moisture with it. This also means skies should begin to gradually clear from west to east as drier air arrives with high pressure from the Plains. 

Flash Flood Watches have been issued for Boone, McHenry and DeKalb counties through Thursday morning, and Flood Advisories and Watches have been issued for portions of the Rock and Kishwaukee Rivers as river levels in some spots rise into 'action' or even 'minor' flood stage.

North winds have been rather gusty for much of the afternoon, at times gusting 35-40mph. Unfortunately, we won't get a break from the wind overnight Wednesday as wind gusts are expected to remain around 35mph through at least mid-day Thursday. Winds will ease Thursday evening as high pressure moves closer to the Stateline, which may lead to patchy fog by Friday morning.

Slow Moving Storm Brings Steady Rain & Flooding Concerns to the Stateline

I wouldn't put the rain gear away just yet. The same storm system that brought scattered thunderstorms to the Stateline on Tuesday, will be behind shower chances we see today.

To get into "the why", we'll have to take a gander higher up in the atmosphere, roughly 16,000 to 18,000 feet up. A slow moving mid-level low is pivoting across the Midwest, while the surface low is currently parked on top of northern Illinois. The mid-level low is going to become what we call "closed off" from flow in the mid-levels by the time it reaches the Great Lakes region. In meteorological terms, a closed off low typically means that there it is incapable of being steered by the mid-level flow. With this low then sitting just to our east, and nothing to steer it away, this is going to place the Stateline in a prime spot for rain chances.

As an abundance of moisture pivots around the surface low, that has already lead to scattered showers and an isolated thunderstorm or two for areas east and northeast of Rockford. Showers are going to become more widespread by late morning, turning into a more steadier rain by this afternoon and evening, with pockets of moderate to heavy rain also possible. This will lead to 1-2" of rainfall in some locations, with totals up to 3" in a few localized areas. And since the region is going to be so close to the surface low, today also features very windy conditions. Winds will pick up our of the north-northwest as we close in on the afternoon hours, and gusts could top off near 30 to 35 MPH. This could lead to loose objects being blown around, and even a few weakly snapped tree branches. As far as when we will see a break from the rain, a few spotty showers may linger into Thursday. But the rainy start will give way to drier conditions by late tomorrow afternoon and evening, but breezy weather is going to persist.

Now, there is a concern for flooding with the rain that we will see over the next 24 hours. For that, the National Weather Service has issued an areal flood watch until midnight Thursday morning. This is for the eastern portions of the viewing area, including Boone, DeKalb, and McHenry Counties in northern Illinois, and Walworth County up in southern Wisconsin.

In these locations, as much as 2" of rain has already fallen. Another 1" to 2" of rain could fall between early Wednesday and Thursday. Once we see this showery stretch come to an end come to an end, rises in rivers and streams are likely, with flooding being a possibility in poorly drained areas.

Thunderstorms Continue Tuesday Evening - Low Risk for Strong to Severe Storms

Scattered thunderstorms have quickly developed Tuesday evening over much of northern Illinois ahead of a cold front and surface low pressure system moving into southwest Wisconsin. The risk for strong to severe storms is still present, but a little more on the lower end following some of the earlier storm activity Tuesday afternoon.

The storms moving through now will have very heavy rain and possibly small hail. There will be a wind risk, as well, with some of the stronger

storms. Thunderstorm activity will continue through 8pm once the cold front comes through. After that, scattered showers will continue through Wednesday morning.

Dense Fog Early, Severe Potential Later On

As if today wasn't busy enough with the potential for severe weather later on, mother nature threw in a layer of dense fog to kick off our Tuesday. Earlier this morning, the National Weather Service did place Green, Rock, & Walworth counties in southern Wisconsin under a Dense Fog Advisory until 10 AM. A few locations here in northern Illinois even experienced less than 1 mile visibility at times this morning. Although we're seeing improvements with the fog, it is expected to stick around into the mid to late morning hours. For those heading out the door this morning, please be sure to drive slowly, and take extra caution if you encounter any dense fog.

Regarding the severe threat later today, it all has to do with a potent area of low pressure that is sliding across the High Plains early this morning. Along with the surface low is a warm front that has been draped to the south of the Stateline all morning. As this low closes in on the Stateline, it will help lift this warm front closer to the IL/WI border by this afternoon, amplifying that severe weather potential. The placement of this warm front is one of the key factors. Most models this morning did push the front in southern Wisconsin, which will allow a warm, and unstable air-mass to roam into northern Illinois. Also, any sunshine we see early on will help heighten that potential.  

After being dry for the first half of our day, model guidance suggests showers and storms beginning to develop during the early afternoon hours, so around 1-2 PM. I think that we will see these storms initiate along the warm front across eastern Iowa, then tracking into western/northern Illinois by late afternoon. While this warm front is going to allow highs across the area to climb near 70° this afternoon, it's also going to add plenty of instability for storms to feed off of.

Per the 8AM update, the Storm Prediction Center has brought the slight risk farther northward into southern Wisconsin, which now includes a majority of our viewing area. In the categories for severe weather, a Slight Risk is a level 2 on a scale of 1 to 5. The main time frame for strong to severe storms for our region will be between 3PM and 9PM later today. There will be a small window for discrete thunderstorms early on, which will be capable of producing all modes of severe weather, including an isolated tornado or two. As the cold front slides into western Illinois by this evening, these storms will then congeal into a line, bringing more of a straight-line wind and heavy rain threat. By 10-12PM tonight, the severe threat will end, leaving few scattered showers into our Wednesday morning.

Now is the time to prepare. As we enter prime severe weather season, it is important to have multiple ways to receive watches and warnings. I know it has been quite a while since we've used our weather radios, but just make sure they are plugged in, and have fresh batteries. Turn up the volume so that you can hear the radio anywhere in the hour once a watch or warning has been issued. Secondly, be sure to have your safe place and severe weather kit ready to go. 

Strong to Severe Storms Possible Tuesday Evening

The risk for strong to severe storms will increase for northern Illinois and southern Wisconsin during the late afternoon and evening Tuesday, bringing a threat for large hail, damaging winds and even isolated tornadoes. Skies will turn partly cloudy during the overnight Monday leading to locally dense fog through early Tuesday morning. Most of the fog should be out by mid-morning with skies turning partly cloudy into the early afternoon.

A few isolated showers will be possible during that time, but the storm threat is expected to ramp up between 3pm and 9pm Tuesday evening. Low pressure will strengthen as it moves from the Plains into Iowa Tuesday afternoon and then into southwest Wisconsin by Tuesday evening. The warm front associated with the low will lift very close to the Wisconsin/Illinois border during the late afternoon and evening. South of the warm front, temperatures will warm into the 70s as moisture

(dew points) increase. Depending on the evolution of storms to the west and how much sun we're able to see before the clouds move back in will determine just how strong storms will be locally.

The first storm activity could arrive as early as 2pm/3pm in northwest Illinois as an upper level disturbance moves in from the west. The second wave of thunderstorms will be likely with the arrival of the cold front between 6pm and 9pm. The greatest risks locally from any storms will be damaging winds, large hail and heavy downpours. However, storms that develop near the warm front could have a higher chance of rotating which may slightly increase the risk for isolated tornadoes.

The Storm Prediction Center does highlight much of northern Illinois and far southwest Wisconsin under a slight risk for strong to severe storms during the afternoon and evening. Make sure to stay updated with the forecast, especially if you're going to be out, and know where to go if severe weather does occur. Most of the thunderstorm activity should be done with by 10pm. Winds will then shift around to the north with a much cooler air mass moving in for Wednesday afternoon. A few wind-driven showers will be likely Wednesday with highs only reaching the mid to upper 50s. 

Locally Dense Fog Possible Tuesday Morning

A few breaks in the cloud cover were found over parts of northern Illinois Monday evening following rain showers earlier in the day. But additional showers and isolated thunderstorms will be possible through 9pm/10pm. After that, skies are expected to turn partly cloudy and with an increase in moisture, locally dense fog will be possible by Tuesday morning which could bring visibility down near zero in some spots just before sunrise Tuesday.

Moisture has been on the increase thanks to a stout southwest wind and rain showers Monday with dew points rising into the mid and upper 40s. The increase in moisture and lighter wind overnight, along with the partly cloudy sky, will allow fog to develop. Most of the fog should be gone by mid-morning with partly cloudy skies expected through the Noon.

Early Week Rain Chances, Severe Potential Tuesday

It's hard to top the gorgeous weather we encountered yesterday, as plenty of sunshine lead to temperatures in the upper 60s. In fact, our high of 67 at the Rockford International Airport snapped the 5 day below-average streak that was currently in place. We'll continue with the spring-like temperatures today, but an addition of shower chances return for the afternoon.


As for this morning, many woke up to the slight of a few peeks of sunshine, and comfortable temperatures in the low to mid 40s. Cloud cover will continue to thicken up, ahead of this afternoon's rain chances. The rain we see later today is all due to a weak disturbance that slides into the region from the upper Midwest. Currently, the heaviest rain with this disturbance is hovering right over the I-35 corridor north of Minneapolis, and across the northern half of Wisconsin. As we get closer towards the mid-day hours, models do suggest that the bulk of this activity is going remain to the north of the Stateline, with only a few light showers here tracking into the area. In terms of timing, shower chances will likely ramp up after the noon hour, continuing through the afternoon. All shower activity will remain light and sporadic in nature, with the window nearly entirely right around sunset.

Although severe weather is not expected today, the potential heightens as we head into our Tuesday. Overnight, a stronger surface low pressure system will help lift a warm front into northern Illinois by tomorrow afternoon. Along and south of this warm frontal boundary will be the areas to watch for the highest severe potential. Highs ahead of that warm front are going to climb into the mid to upper 60s, with toasty 70s on the backside of the front. If highs do manage to climb into the 70s, that will only help fuel and heighten the threat for severe storms. As dew points at the surface rise close to 60°, storms will definitely have a good amount of moisture and instability to tap into.

As of early Monday morning, the Storm Prediction Center is keeping an eye on that warm front, as they have extended the Slight Risk (level 2 of 5) northward into northern Illinois, with our counties in southern Wisconsin under a Marginal Risk. Any storm that does take advantage of this unstable environment will have the capability of producing strong winds, large hail, and tornado development.

Now, there are two key components to determine the potential during the day tomorrow for the Stateline. The placement of that warm front, and the amount of sunshine we see during the day. By midnight on Wednesday, the threat for severe weather is going to be wrapping up as slightly cooler temperatures work into the Stateline for midweek. Along with the cooler temperatures are a chance for showers as moisture wraps around the backside of the low. As a friendly reminder, be sure to have a severe weather plan ready to go, and to have multiple ways to receive watches and warnings.

Sunday's Sunshine Gives Way to More Clouds and Rain Monday

Plenty of sunshine and warmth Sunday afternoon after a rather rainy, cloudy and chilly Saturday afternoon. Highs area wide Sunday warmed into the mid and upper 60s, after temperatures Saturday only made it into the upper 40s. Skies will remain mostly clear through much of Sunday, outside of a few fair weather cumulus clouds over northwest Illinois. Showers and isolated thunderstorms have developed further to the northwest over parts of Wisconsin, Minnesota and northeast Iowa as an upper level disturbance moves southeast during the day. That disturbance will slide southeast, but continue to weaken as it does so.

Cloud cover will increase during the morning Monday as another, stronger, system moves in from the northwest. This main forcing with the low will remain to the north over Wisconsin, but increasing showers mid to late morning will be likely from southern Wisconsin to northern Illinois. Scattered showers will likely continue through the afternoon. Highs Monday will warm into the low 60s.

A stronger storm system is set to move in Tuesday with a chance for showers and thunderstorms during the afternoon and evening. Depending on how far north the warm front came make it, a few stronger thunderstorms will be possible during the evening. 

Remaining Cloudy & Gloomy, Rain Chances into the Weekend

Yesterday, we saw the return of scattered showers during the afternoon, and then again overnight last night. Altogether, the Rockford International Airport observed .30" of rainfall. This is now the second highest daily rainfall during the month of April, second to the .39" of rain that was observed back on the 12th. Shower chances aren't completely over yet, as more rain and cool temperatures persist into the second half of the week.

Last night's shower activity did leave us with a good amount of cloud cover, and areas of patchy dense fog. So far this morning, the thicker areas of fog have been confined to locations north and west of Rockford. A few locations, such as Monroe, Freeport, and Galena, have observed visibility under a mile all morning. For those that are set to step out the door and travel, take a little bit of extra time getting to your destination. It is possible that the fog could linger into the mid-morning hours.

Despite this fog and cloud cover, most regions remain dry through noontime. Rain chances ramp up into the afternoon and evening, as a few spotty showers look to develop across the Stateline. Current thinking suggests around the 3-4 PM time frame, scattered showers will begin to pop up across the area. Fortunately, rain totals with these showers are going to remain fairly minimal. Along with the cloudy skies and scattered shower activity, today will feature cooler temperatures. Winds this afternoon will be dominate out of the northeast, which will limit highs for most locations to near the 60° mark.

More rain chances are in the forecast as we close in on the weekend, as rain is expected to move in during Friday afternoon. Due to the cloud cover and chances for more rain showers, temperatures for the end of the work week will end on a below average note. Highs, because of the lack of daytime heating, will only climb into the upper 50s. As a stronger system that originates over the southern plains, will track to the south of the Stateline by Saturday morning, allowing rain chances to persist through the overnight hours into early hours on Saturday. During this time frame, pockets of heavy rain are possible, along with a with the chance for a few rumbles of thunder. Once again, severe weather isn't expected. By the 2nd half of Saturday, rain chances will look to move out of the Stateline, leaving behind drier and cloudy conditions.

Showers and Thunderstorms Increase Wednesday Evening

Scattered showers and thunderstorms developed late morning Wednesday and lasted through much of the afternoon, but began to taper off between 4pm and 6pm. There remains quite a temperature spread across northern Illinois and southern Wisconsin, with temperatures across NW Illinois warming into the 70s, while areas further east and north stayed in the 50s and low 60s. That difference was all thanks to a very strong warm front draped from low pressure over Minnesota, stretching down through Iowa and Illinois.

Thunderstorms were quick to develop over northeast Iowa, stretching east into southwest Wisconsin and into a slightly more stable air mass. This line of storms is generally moving east, but also south and further into southern Wisconsin and northwest Illinois. The intensity of the storms continues to weaken, but our chance for showers and isolated thunderstorms will increase between 7pm and 9pm. Severe weather is not expected, however, heavy downpours will be possible.

The shower and storm chance will last through 1am/2am Thursday morning with lingering showers expected through the rest of the morning. Skies will remain mostly cloudy Thursday with highs warming only to the upper 50s and low 60s.

Warm Temps Return, Along with Rain and Storm Chances

After Rockford posted the 4th wettest March on record, rain has been a little scarce during the month of April. In fact, the airport has only recorded 1.27" of rain since April 1st, which puts us just over an inch below average. An unsettled weather pattern begins today that will bring several rain chances to the Stateline that extend into our weekend.

Before we get into the forecast, Happy Earth Day Stateline. Virtually supporting Earth Day with a lot of green in this blog post. A quick-moving disturbance that is currently residing over the South Dakota/Minnesota border brought a much different start to our day today. For those that stepped out the door this morning, they were most likely greeted by a few light sprinkles and light rain showers on their way to work. Fortunately, this activity has remained fairly light in nature. The rest of the morning does feature chance for an additional isolated shower or two, but the steadier and more substantial rainfall holds off until later in the afternoon.

Along with this disturbance is a warm frontal boundary that is draped over eastern half of Iowa. This front has caused quite the temperature difference across the Hawkeye State this morning, with upper 30s in Cedar Rapids, and mid 50s just to the west in Des Moines. As we progress into the afternoon, this frontal boundary will be the focus for not only how warm temperatures get across the area, but also for storm development. South of that warm front, temperatures should be nice and toasty in the 70s, while north of that front, highs may struggle to get out of the 50s.

Shower activity looks to pick after 3PM-4PM this afternoon, with heavier rain and t-storm potential by this evening. It would definitely be wise to bring the umbrella with you this morning, so that you have it ready to go when rain chances increase later today. This evening's storm activity seems to persist into the first half of our night tonight, as pockets of heavy rain and lightning are likely. There is also the potential for gusty winds with the stronger storms, but severe weather is still not expected.

A few spotty showers may linger into Thursday morning, but most of the day looks to shape up pretty dry. Northeasterly winds will pull an abundance of moisture off of Lake Michigan, allowing cloud cover to stick around, with a few breaks possible here and there by the afternoon. Highs are going to be a tad cooler, with most areas only getting into the 50s to near 60°.

Sunny and Cooler Today, Rain Chances Begin Tomorrow

Temperatures during the month of April have been on a legit roller coaster ride thus far. Before we hit a high of 64° yesterday, the Rockford Airport experienced 7 days straight with below average temperatures. As far as what to expect today, the cold front that slide through the area yesterday has brought a cooler air-mass for our Tuesday. You won't necessarily feel this expected cool down heading out this morning, but definitely by the afternoon.

Temperatures to start this Tuesday morning are starting in the 30s, with wind chills during the mid to upper 20s. For those "deemed" essential or those going for an early-day run, dress warmly before stepping out the doorway. As an area of high pressure sits comfortably over the Midwest, this will continue to bring chilly northwest winds to the Stateline this afternoon. And they could be a bit gusty at time. Thankfully, not as gusty as winds were yesterday, but a few locations could observe wind gusts upwards of 25-30 mph. The insertion of this cooler air-mass will lead to highs in the low 50s, which is what you typically see as an average high for late-March. The positive to today's forecast, this high pressure system will keep our skies sun-filled into this evening.

Now, don't panic. This cool down won't last too much longer. A warm front is expected to lift into northern Illinois by Wednesday morning, bringing more seasonable temperatures to the Stateline, as highs will climb back into the mid-upper 60s. These warmer temperatures could help in the development of scattered showers by Wednesday afternoon, and even a chance for a embedded thunderstorms by late in the day. Model guidance continues to hone in on a line of gusty thunderstorms that move in towards the late evening hours, very similar to what blew through the region Monday evening. Conditions should begin to taper off early tomorrow night, leaving skies mostly cloudy into Thursday morning. Enjoy the sunshine today Stateline!

Gusty Showers Move In Monday Evening

A line of gusty rain showers will continue to move southeast into northwest and north-central Illinois this evening, impacting areas like Rockford, Roscoe and Belvidere between 6:30 and 7:30pm. These showers have developed along a cold front that will move through later this evening.

Severe weather isn't expected, but with such strong winds in the atmosphere some of the heavier showers could help transport the stronger winds aloft down to the surface, causing winds to gust near 50mph at times this evening. Most of the rain activity will winding down after 10pm with skies clearing through Tuesday morning.

Sun-filled Morning will Lead to Late-Day Showers

Following a gorgeously warm weekend, conditions around the Stateline got a little chilly this morning. Chilly enough to where those that are deemed essential definitely needed to grab the heavier jacket before leaving the household. The combination of clear skies overnight and very light surface winds, allowed for lows to register in the upper 20s-low 30s in all locations. Thankfully, plenty of sunshine came along for the ride with today's chilly beginning. Sunshine will continue to fill our skies throughout the rest of the morning, before clouds and shower chances return Monday afternoon.

Despite this morning's chilly start, gusty winds ahead of an approaching cold front are forecast to pick up by mid-afternoon. These gusty west-southwesterly winds will allow temperatures to climb into the low 60s for the second straight day. We are already seeing a decent spike in temperatures, as most spots have warmed into the upper 40s. Winds at times this afternoon, and even into this evening, could gust upwards of 30-35 mph. Thankfully, not as strong as winds were on Saturday. But definitely strong enough to blow around any light weighted objects in your yard.


As far as when shower chances develop, showers should begin to pop up during the afternoon and evening hours, with pockets of heavier rain possible. The heavier rain may be accompanied by a few rumbles of thunder, though no severe weather is in the forecast. By midnight Tuesday, rain tapers off as the cold front sweeps through the Stateline. However, this will bring cooler weather for our Tuesday.

Following this cold frontal boundary, conditions will dry out rapidly, leading to yet another chilly and sun-filled morning. Nothing different from what we're seeing this morning, but it's during the afternoon when you're going to really feel the difference with this expected cool down. Highs tomorrow afternoon are only going to climb into the low 50s, a solid 10°+ below average. While Tuesday may feature a bit of a chill, by midweek, a warm front will help put an end to this short-lived cool down. Wednesday through Friday feature high temperatures into the lower and middle 60s.

Rain Monday Evening Following a Warm and Windy Afternoon

Temperatures Monday will warm back into the low to mid 60s as southwest winds gust close to 30 mph during the afternoon. Much of the afternoon is looking dry ahead of a cold front that will move southward during the afternoon and evening. Showers are possible ahead of the front between 5pm and 7pm, but a line of showers and isolated thunderstorms are even more likely as the front approaches southern Wisconsin and northern Illinois late Monday evening.

The timing of the front, however, isn't very favorable for thunder activity, although a rumble or two can't be ruled out. The rain that moves in should be quick, approaching southern Wisconsin between 7pm-8pm and then northern Illinois between 8pm and 10pm. Skies will dry once the front passes after Midnight as the wind shifts to the northwest by Tuesday morning. Rainfall totals will remain light, with most areas receiving under a quarter of an inch. High pressure will then move down the Plains during the day Tuesday with highs warming into the mid 50s for the afternoon.

Warmer and (Somewhat) Drier This Weekend

After receiving three inches of snowfall on Friday morning in Rockford, setting the record for the snowiest April 17^th , a drastic warmup is expected this weekend.

By early Saturday morning, a large high pressure system will have situated itself to our south over the Missouri Valley. Simultaneously, a strong are of low pressure will be centered over west-central Ontario. As a result, a tight pressure gradient will form over much of the Midwest, including northern Illinois. This will produce strong southwesterly winds through the day on Saturday resulting in strong warm air advection. Temperatures on Saturday are forecast to reach the upper 50’s by the mid-afternoon. The continental tropical air mass will dry out the atmosphere enough to expect only light cloud cover overhead meaning plenty of sunshine and no rain or snow are expected on Saturday.

A weak cold frontal boundary extending from the previously mentioned low pressure system will approach late Saturday evening. As it moves over the Stateline overnight and into early Sunday morning, a chance for rain is expected in the predawn hours of Sunday and through the early afternoon. An approaching high pressure system from our northwest following the frontal passage should clear up most of the cloud cover shortly after the chance for rain recedes. With the passage of a weak cold front and mostly cloudy skies in through the morning has us expecting temperatures to be a couple of degrees cooler than on Saturday but still climbing into the middle to upper 50’s through most of the area.