Tranquil weather settles in following Wednesday's heavy rainfall

Wednesday's rainfall was a healthy one, leaving locales with .75" to 1.12" of rain. This puts us well ahead of schedule in terms of seasonal rainfall and closer to our average for the year.

 

 

Moving forward, your umbrella and windshield wipers can take a break as we aren't expecting any "washout" type rainfall in the coming days. Behind yesterday's potent storm system, tranquil weather settles in, though we look to hold on to a bit of cloud cover and a breeze. The strongest winds today will be felt before lunchtime with gusts ranging from 25 to 30 mph. This will dial back our afternoon highs, leaving most in the low to mid 50s.

More clouds build into the region Friday as a weak low pressure system tracks to our south. With this cloud cover will be the chance for an isolated sprinkle or shower during the afternoon.The combination of the cloud cover, the small chance for rain, and the light breeze out of the east-northeast will leave high temperatures in the low 50s. This storm system will be slow to track east, leaving cloud cover and a small chance for a sprinkle or shower in place Friday night into the first few hours of Saturday.

Wednesday afternoon storm update

9:30pm Update: The severe threat has ended for us this evening as a cold front approaches from the west. This will shift our winds from the south this evening to the west through the night, and then from the northwest Thursday afternoon. High temperatures will warm into the mid-50s under partly sunny skies.

12:50pm Update: The showers and storms from Wednesday morning continue to move out but some additional thunderstorm activity has moving through Lee, Ogle, and DeKalb counties. The biggest threats at the moment with these storms will be heavy downpours and gusty winds.

These storms remain north of a warm front which currently stretches across central Illinois where temperatures are in the 70s, but in the 40s and 50s north of the front. The Storm Prediction Center has shifted the highest risk for severe storms this afternoon further southeast, with northern Illinois now under a 'marginal' risk - meaning more isolated severe potential.

Trends have been pointing in the downward direction with the severe threat locally, but we're not out of the woods just yet. Clearing skies out west of the Mississippi River in Iowa will allow for some instability to build throughout the afternoon, shifting east by mid-afternoon. This will likely allow for at least some storm activity to redevelop locally by mid to late afternoon.   

Early morning update on today's severe potential across northern Illinois

The first of potentially two rounds of strong to severe thunderstorms has it's eyes set on northern Illinois as we approach sunrise. All non-severe at the moment, but could pose a threat for hail up to 1" in diameter, damaging winds, and heavy downpours from sunrise until about 10AM-11AM. 

 

 

The longevity of this morning's activity will tell the tale for the potential for a secondary round this afternoon and evening. Do storms exit in a quicker fashion, allowing time for the atmosphere to recover or recharge? And if storms do manage to form, we'll have to see if they are able to sustain themselves, keep their strength as they quickly move into the area. Or are they slower to exit, which would significantly lower our severe potential. If redevelopment does occur, the main window will be from 2PM-8PM, with all severe hazards being in play. 

In their latest round of outlooks, the Storm Prediction Center dropped the Level 3, Enhanced Risk to the south of Rockford. Included is DeKalb, Rochelle, and Sterling. North of that line, a Level 2, Slight Risk for severe weather is in place. 

Again, it will be very very important to have multiple ways to get watches and warnings. Not only this morning, but also during the afternoon hours in case we do see redevelopment. 

After the cold front pushes through, we cool down for Thursday. We start off the day similar to this morning with temperatures near the 40° mark, though a more westerly wind will place highs in the upper 50s. Skies should remain partly cloudy throughout the day as an area of high pressure sits to our north. Temperatures remain in the mid 50s for Friday, though clouds will increase into the afternoon as our next rain-maker approaches from the southwest.

Latest on the severe potential Wednesday

 

We are about to settle into what could be an active weather pattern over the next 24-30 hours, so let's dive in:

Rest of this afternoon/evening:

Cloudy skies will remain in place through the evening as a few light sprinkles/scattered rain showers develop. Radar shows the light rain overhead, but very little of that is reaching the ground thanks to some low-level dry air. Along and north of the state line there will be some light snow showers mixing in. Impacts should remain minimal with any snow showers that do develop.

Overnight:

The precipitation this evening is the result of an elevated warm front moving into the Midwest. The surface warm front and low-pressure system will move closer to the region through the overnight. This will result in scattered thunderstorms beginning to develop after 2am/3am. These storms will remain elevated, posing a risk for hail. Isolated hail stones reaching one inch in diameter could occur, so an isolated severe threat remains through sunrise Wednesday.

Wednesday morning:

Ongoing showers and thunderstorms can be expected. Heavy rainfall will make the morning commute slow, so be sure to plan accordingly. There is still the risk for hail, but also a gusty wind threat or two.

A 'marginal' risk for an isolated severe storm or two is in place area wide for late Tuesday night/Wednesday morning.

Wednesday afternoon:

The focus will then shift to the storm potential during the afternoon. And this is where it gets a little complicated....

The severe risk for Wednesday afternoon remains conditional on what happens Wednesday morning, and unfortunately that leads to some bigger questions. So, here's the breakdown...

Our window for afternoon storms will range from about 12pm/1pm - 7pm/8pm. Even if the morning storm activity is a bit slower to leave, the strong upper-level dynamics of this storm system may be able to overcome some of that, allowing to a quick recovery and build up of instability. If that does occur - our risks with storms Wednesday afternoon would be damaging winds and large hail. However, the tornado risk is there (and could grow) if conditions are just right.

However, there is also the chance that we still see storms redevelop but on the weaker side which would give us less of a severe potential.

I'll be honest - if everything does come together the risk for big thunderstorms is there. And that's why I'm kind of hitting on this potential a little more. I want to make sure you are aware of that risk should you need to act. The storms will be moving at a very fast pace, which wouldn't allow for much time to react.

Wednesday late evening:

The cold front passes and we see drier conditions into the overnight.

So, here's our timeline:

Morning storm activity: 3am-late morning

Afternoon storm activity: 12pm/1pm - 7pm/8pm

Make sure you're checking in on the weather Wednesday morning with Meteorologist Joey Marino. Him and Meteorologist Owen Szarley will be in monitoring the storms during the morning. Be aware that afternoon storms could quickly develop Wednesday, and make sure you have a plan of action should you need it.

Tuesday morning update on Wednesday's severe storm potential

Tuesday:

Tuesday will be very similar to Monday, though we'll see the opposite in terms of cloud cover. Skies will cloud over following a sunny start to the day, leaving us mostly cloudy by the afternoon. Despite the cloud cover, an organized southeasterly wind will help bring afternoon highs back near the 50° mark.

Tuesday night: 

Towards the beginning of the evening commute, a few sprinkles and light rain showers will develop as warmer air pushes into the region. 

It's not out of the question that some of our locales, especially those along and north of the Illinois/Wisconsin border, may end up cold enough for a few flakes to mix in. Thankfully, accumulations and travel impacts are not expected. From there, light rain showers will continue in a scattered fashion through the rest of the evening and into the early stages of Wednesday morning. In response to the incoming deepening low, winds will also increase during this time. Expect peak gusts to range from 25 to 30 mph this evening, then closer to 40 mph after midnight. 

Wednesday Morning:

Isolated to scattered severe storms will be possible during the early morning hours Wednesday as the remnants of storms that develop late Tuesday evening over the Plains shift east-northeast.

These storms may still be strong enough to produce large hail up to 1" in diameter. Timing remains the same, with the main window starting up just before sunrise, with potential lingering into the late morning hours. Overnight, the Storm Prediction Center downgraded the Stateline from a level 2 of 5, Slight Risk to a level 1 of 5, Marginal Risk.

Wednesday Afternoon:

A secondary round of strong to severe storms remains possible Wednesday afternoon, though it will all depends on what occurs Wednesday morning. 

If the morning activity is slower to depart, it would likely limit our atmosphere from recharging. If, however, the storms are faster to move out and the cold front is slower to move in then our severe threat during the late afternoon and evening would increase with all hazards on the table. 

Right now, it looks like the morning activity lingers into midday which again, if that were to happen would lower our severe potential for the afternoon. Then again, it doesn't take much solar radiation with these early-spring setups for the atmosphere to recharge. In their latest round of severe outlooks, the Storm Prediction Center has left most of northern Illinois under a level 3 of 5, Enhanced Risk. Storm chances drop Wednesday evening as the cold front pushes east, leaving us quiet and mild for Thursday.