Important: Severe weather update Sunday night and Monday

The Severe Thunderstorm Warning for Winnebago County has been canceled - Severe Thunderstorm Warning continues Boone, Ogle, DeKalb and McHenry counties until 6:45am.

There have been numerous reports of power outages, along with numerous reports of downed trees in and around the area.

Severe Thunderstorm Warning now until 6:45am for the following counties: Boone, DeKalb, Ogle, McHenry and Winnebago.  Storm is capable of producing wind gusts to 60 mph through the morning.  This is a very dangerous thunderstorm, and while rotation hasn't been overly strong with this storm, damaging wind gusts are more than likely.






Very strong wind gusts to 55mph - 60 mph with incoming storm from Rockford, Loves Park & Machesney Park.







(5:34:13 AM) nwsbot: Local Storm Report by NWS LOT: Harvard [Mchenry Co, IL] trained spotter reports TSTM WND GST of M63.00 MPH at 05:30 AM CDT --

(5:22:45 AM) nwsbot: Local Storm Report by NWS MKX: Richmond [Walworth Co, WI] law enforcement reports TSTM WND DMG at 05:00 AM CDT -- tree down across road.

A Severe Thunderstorm Warning has been issued for Winnebago, Boone and McHenry counties until 6am.  Wind gusts to 60 mph are possible with this line of storms.  Seek shelter and remain in doors until the storm passes.  This line is moving to the southeast around 35 mph.

A Severe Thunderstorm Warning has been issued/extended for Green, Rock and Walworth counties until 5:30am.  This line of storms was located near Scales Mound and moving southeast at 70 mph.  Wind gusts to 60 mph are possible.  The leading edge of these storms will be crossing over the Illinois/Wisconsin border around 5am.




A Tornado Warning has been issued for Dodge County Wisconsin until 4:45am.  Radar continues to indicate rotation within the leading edge of the squall line in Wisconsin, and damage has been reported in Columbus, Wisconsin.  Multiple trees have been reported down.




A Severe Thunderstorm Watch has been issued until 10am Monday morning Green, Rock, Walworth, Winnebago, Boone, McHenry, Ogle, Lee, Stephenson, Carroll, Jo Daviess and Whiteside counties.

Severe Thunderstorm Warning for Rock and Green counties in southern Wisconsin until 4:45am.  Squall line of thunderstorms is currently moving southeast around 45 mph.  Wind gusts to 70 mph are possible.  Remain in doors and away from windows.

9:25pm Update:  Current forecast looks on track.  Storms in Minnesota are now developing into a damaging wind threat and will continue to track southeast into Wisconsin over the next few hours.  A weather watch will likely be issued east into Wisconsin and southwest Wisconsin.  We'll also be watching the potential for thunderstorms to develop in the very moisture rich atmosphere ahead of the main storm complex through Midnight.  Large hail, should those storms form, would be the biggest concern.

This image to the left is a simulated radar image for 6am Monday morning.  Should this model verify, the damaging wind threat would hold through southern Wisconsin and northern Illinois through 8am. 









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Not only is the weather going to feel like summer, but we've also got some big-time summer thunderstorms to talk about, beginning as early as tonight.

Storms continue to quickly fire up in Minnesota with numerous tornado warnings in place.  Those storms will remain northwest of Northern Illinois through the rest of the evening and early overnight.  Once we get after 1am - 3am, the likelihood of storms moving in increases.  Now, normally we talk about storms losing their strength once the sun sets because we're losing the heating of the day.  That's not going to be the case tonight.  Instability in the atmosphere will remain fairly strong and high through the night helping feed storms as they move southeast into Wisconsin, Northeast Iowa and Northern Illinois.

Because of that, the Storm Prediction Center has much of Northwest Illinois and Southwest Wisconsin highlighted under an Enhanced Risk for severe weather through 7am Monday morning.  Storms will likely move into our air space after 3am and remain through 8am or 9am.  Heavy rainfall and strong winds are going

to be the primary threats.  Strong winds, especially, if a bowing line of storms develop.

The National Weather Service has issued a Flash Flood Watch for much of North-Central Illinois for the potential for training thunderstorms not only Monday morning, but also Monday afternoon and evening.  If you've stepped outside at all Sunday, you've noticed an increase in the humidity.  That humidity will only grow through the day Monday as our dew points climb higher with southwest surface winds.

Also, a Heat Advisory has been issued for Carroll and Whiteside counties to begin at Noon on Monday and last through 7pm Monday evening.  There, heat index values could climb as high as 100 degrees!  All of that moisture in the atmosphere may lead to flooding rain on Monday.

Now, our attention will turn to what *could happen Monday afternoon and evening.  The Storm Prediction Center has, again, Southern Wisconsin and Northern Illinois highlighted under an Enhanced Risk for severe weather, but also a Moderate Risk just to the east of Rockford - including the counties of DeKalb, McHenry, Ogle and Lee.  There is the potential for a widespread severe weather outbreak, and I want to stress the word potential, very close to the area on Monday.

Atmospheric signals are beginning to point to certain things coming together in order for severe weather to occur.  However, this IS NOT set in stone.  And the reason I say that is because Meteorologists have the capability to look at past weather events with similar set ups to what will occur Monday, to get an idea of what could potentially happen.  And while many have produced severe weather in and around the area, there have also been many that haven't.  So, bottom line is this:  Storms are likely a good bet again Monday late afternoon.  Where and when they exactly develop will be dependent upon what morning storms do to our atmosphere.

The instability will be in place.  And if cloud cover can clear enough and leftover boundaries from storms Monday morning are placed just right, storms will quickly develop late afternoon and turn severe.

A possible scenario for Monday is this:  Individual storms redevelop across Southern Wisconsin during the afternoon, possibly between 2pm and 4pm.  Those storms form into a line of storms and race east/southeast into Illinois and Eastern Illinois during the late afternoon and evening hours holding on to a damaging wind threat, possibly tornado threat.  Storms move out of our area after 8pm Monday evening.

Again, storm redevelopment Monday afternoon/evening depends on how our atmosphere 'recharges' following thunderstorms from the morning.  Before you go to bed tonight, make sure your volume is turned up on your phone and/or your weather radio has batteries.  This way, should warnings be issued overnight, you'll be able to hear them and take the necessary precautions.  Monday morning, make sure you join Meteorologist Kristin Cwynar for not only an update on the storms in the morning, but also the likelihood of storm development later in the day.

As we head into the evening, any new and updated information will be passed along right here.  So keep this page bookmarked.