Active pattern with increased potential for severe weather next week

 Another stretch of active weather looks to develop next week as we get a pattern flip in the upper levels of the atmosphere. A Southwesterly direction of flow will develop, allowing a large area of the country to see an influx of warm and moist air. This will set the stage for a few rounds of severe weather toward the early half of next week.

While the timing of each individual wave is yet to be determined, the ingredients for active weather, including severe weather, will be there. Two of the primary ingredients include strong jet stream winds and instability, or storm energy. Both of those primary ingredients will be present early next week, fueling a multi-day risk for severe weather across the Plains and Midwest.

The Storm Prediction Center has already highlighted portions of the Stateline for severe weather potential for three straight days next week: Monday, Tuesday, and Wednesday. The 15% risk stands for 15% chance to see severe weather within 25 miles of a point, which is equivalent to a Level 2/5 Slight risk at this time. Each risk for severe weather will have its own individual timing and primary threats, but it is significant to see a multi-day risk like this more than a few days out. As confidence of each wave grows, be sure to stay tuned for the latest and remain weather aware next week!

Periods of heavy rain expected Thursday night

 

6:52PM UPDATE: Light to steady rain continues to move across northern Illinois this evening. Over the next hour some of the showers may begin to lighten up, but a steady and heavier rain will move in closer to 9pm.

Skies were sun-filled Thursday morning and most of Thursday afternoon following widely scattered rain showers late Wednesday night. But now the cloud cover has filled back in, leaving skies mostly cloudy to cloudy with rain beginning to move in from the west and southwest.

These showers are forming along a frontal boundary that'll slowly lift back to the north as weak low pressure moves in from the west. An increase in both moisture and wind will allow the rain to become widespread as it overspreads northern Illinois and southern Wisconsin by 6pm, with pockets of heavier rain expected by 8pm/9pm.

Totals are likely to range between half and three quarters of an inch, but there could be some locations that receive an inch, or more, by Friday morning. Following the heavy rain and flooding from late last week, there is a risk of more localized flooding with Thursday night's rainfall. Especially with the already saturated ground and rivers, creeks, and streams running high. This will raise at least a localized flooding risk tonight.

Most of the rain will be wrapping up by Friday morning but a few lingering showers may still be around through sunrise. High pressure to the north during the afternoon will leave us with a dry Friday but temperatures slightly cooler than what we've felt the last few days. Dry conditions will continue into the start of Saturday, but as another warm front nears the region the chance for a few scattered showers and thunderstorms will be possible during the afternoon, and especially during the evening and overnight.

Turning cooler with rain on the way tonight

Windy Wednesday:

Yesterday was an VERY windy day across northern Illinois. Strong southerly to southwesterly winds frequently gusted between 30-40 mph, helping much warmer air spill in. Thanks to that wind, temperatures surged well above-average compared to early-April standards, climbing into the low 70s.  

    

Cooling down:

Today and tomorrow won't nearly be as windy, but we will see a noticeable change in our weather pattern as a cold front surges southward. Even with that front, highs today remain slightly above-average in the low 60s. By Friday, cooler air settles in thanks to a north to northwest wind, bringing afternoon highs closer to normal leaving most in the upper 50s.  

Rain Chances Tonight:

Rain chances slide back in this evening, starting off light but becoming more organized and widespread as the we get into the overnight hours. Along with steady rain, a few embedded storms will be possible, though severe weather is not expected. 

  

Most areas should pick up a quarter to three-quarters of an inch, with isolated totals up to 1". The good news, coverage should wind down just before the start of the morning commute, setting the stage for a damp but improving start to the day.    

Strong winds continue Wednesday evening ahead of cold front and rain showers

 

11:00PM UPDATE: Steady rain continues to fall for some across Winnebago and Ogle counties Wednesday night, with additional showers found back to the northwest. The rain won't last too long in any one given location as the main line is moving east and northeast. Rainfall totals will remain under a quarter of an inch and will be wrapping up just before daybreak Thursday.

Southerly winds have been rather strong Wednesday afternoon gusting as high as 45 mph in a few locations. The winds will remain gusty through most of the evening, easing only when a cold front comes through after Midnight.

Ahead of the front rain showers have developed, moving from northeast Iowa into southwest Wisconsin. Some of the stronger showers have been capable of producing wind gusts around 50 mph,

pulling down some of the stronger winds aloft. Over the next couple of hours most of the rain will be to our west, with showers now extending across far northwest Jo Daviess County. But as the front begins to move east the rain will as well, spreading over most of northern Illinois between 8pm and 11pm. Scattered showers, with maybe a rumble of thunder or two, will continue through the night with around a quarter of an inch of rain falling by Thursday morning.

The front will sink south of the Stateline during the day Thursday taking the rain showers south with it. West winds will bring temperatures back into the low 60s for the afternoon. The front will then be pulled back north Thursday evening as showers and embedded thunderstorms overspread the region. Some heavier rainfall will be possible during that time (Thursday night) with rainfall totals adding up between half an inch to three quarters of an inch Friday morning. We'll dry things out for a couple days before the next chance of rain (and storms) moves in by the weekend.

Gusty winds return ahead of an unsettled stretch

Quite the Difference:

A tightening pressure gradient ahead of our next cold front will set the stage for a much warmer day. High temperatures Tuesday wound up in the low 40s, landing 12 degrees below average. But with the help of a little sunshine but more importantly, a robust south to southwest wind, we can expect afternoon highs to wind up in the upper 60s today.  

Timing of Strongest Winds:

The strongest winds are expected to arrive during the afternoon hours as daytime mixing increases and taps into the stronger winds aloft. 

Gusts will likely peak during the mid to late afternoon hours, with some locales seeing gusts approaching 40 mph. These winds will likely make it difficult for high-profile vehicles and could cause a few loose objects to be blown around, so it's good idea to secure any lightweight objects. Winds are expected to gradually ease as we progress through the overnight hours.  

Rain Chances Return:

As a cold front sweeps through tonight, it will bring the chance for a few rain showers, though coverage locally will be fairly isolated. The better potential for rain seems to end up north of the Illinois-Wisconsin border where moisture and lift will be a bit more favorable for shower development. An isolated storm or two cannot entirely be ruled out.  

More widespread rain will arrive late Thursday into Thursday night as a stronger system approaches. Rain will increase in coverage from west to east, initially starting off light. As the night goes on, heavier rain and even a few thunderstorms will sweep through the area (all non-severe). Rain should taper off during the mid-morning hours, with many locations picking up between .50" and 1.0". Additional rain chances are scheduled to move in over the weekend, with the best opportunity coming in late Saturday. 

A brief return of wintery weather Tuesday night

 The sun-filled skies we were dealt Tuesday afternoon were much appreciated, but it didn't do much to warm our temperatures as most remained in the low to mid 40s. Rockford reached 44 degrees, 12 degrees below our daily average. But we will feel a quick warm up Wednesday as winds turn to the southwest giving temperatures a nice little boost back into the mid and upper 60s. With the return of the warmer air, however, there will also be a return of some light precipitation.

Cloud cover will continue to thicken up through the evening as moisture slowly increases from the south and southwest. Temperatures will drop back into the low to mid 30s early in the evening before climbing back close to 40 by sunrise Wednesday. 

An upper-level disturbance will move in from the west bringing with it a chance for some light precipitation late evening and overnight. Initially, we may see some light snow at the onset as temperatures near the surface will be close to freezing. But as those numbers begin to climb a transition over to sleet, and then eventually light rain, will occur after Midnight. I do not anticipate any accumulation of wintry weather or impacts on the roads as anything that does fall will be rather light and surface temperatures warm enough to prevent much of anything from sticking. And as for the rain, totals of less than a tenth of an inch are expected.

Most of the precipitation will be wrapping up around daybreak Wednesday. Temperatures will have warmed into the low 40s as winds turn to the southwest. Wind speeds will pick up throughout the morning, gusting around 35 mph throughout the afternoon. This will help bring temperatures into the mid and upper 60s for the afternoon. The chance for rain will return Wednesday late evening and overnight ahead of a cold front that'll move in from the west and northwest. Rainfall totals from Wednesday night through Thursday morning will range from a quarter of an inch up to half an inch.

Gusty winds help bring a big warm-up across northern Illinois

More Wind Inbound:

Meteorological spring has certainly made its presence felt as it's been a notably windy start to the season. Through the first month and a week, the airport has observed 27 days with peak winds between 20 to 39 mph along with two high-impact days where winds soared above the 60 mph mark. 

  

Looking ahead, the wind briefly takes a break today, with lighter breezes allowing for a calmer feel across the region. That quiet period will be short-lived as winds will ramp up again Wednesday ahead of our next frontal passage. At times, gusts may climb into the 35-40 miles-per-hour range. Those stronger south to southwesterly winds will play a massive role in a more significant climb in temperatures, sending afternoon highs from the mid 40s today to the upper 60s by Wednesday afternoon.  

Active to the South:

With the jet stream to the south late this week into the upcoming weekend, severe weather potential will be best across the southern plains. The Storm Prediction Center has highlighted a 15% (Slight Risk equivalent) for portions of Texas on Saturday, then for portions of Texas and Oklahoma Sunday. 

   

The window for any severe weather potential across northern Illinois doesn't appear to arrive until the late Sunday-Monday time frame. At this point, potential remains uncertain as the forecast will go through several changes over the coming days. For the time being, the Storm Prediction Center has highlighted a 15% risk area for Monday, stretching from central Texas northward into southern Iowa.