Thursday's Storms: All you need to know

The storm threat is over.  It's just the strong wind we've got to be concerned with tonight and Friday.  We'll have continuous, live coverage first thing Friday morning at 5am




(8:33:08 PM) nwsbot: Local Storm Report by NWS LOT: Woodstock [Mchenry Co, IL] trained spotter reports HAIL of quarter size (M1.00 INCH) at 08:28 PM CDT -- fleming road and bull valley road(

8:21:28 PM) nwsbot: LOT issues Severe Thunderstorm Warning [wind: 70 MPH, hail: 1.75 IN] for La Salle [IL] till 8:45 PM CDT
(8:21:46 PM) nwsbot: LOT issues Severe Thunderstorm Warning [wind: 70 MPH, hail: 1.25 IN] for Lake [IL] till 8:45 PM CDT
(8:22:17 PM) nwsbot: LOT cancels Severe Thunderstorm Warning for Kane, Ogle, Winnebago [IL]
(8:22:18 PM) nwsbot: LOT continues Severe Thunderstorm Warning [wind: 60 MPH, hail: 1.25 IN] for Boone, De Kalb, McHenry [IL] till 8:30 PM CDT
(8:23:22 PM) nwsbot: Local Storm Report by NWS LOT: Woodstock [Mchenry Co, IL] amateur radio reports HAIL of quarter size (E1.00 INCH) at 08:17 PM CDT -- troop st and kishwaukee.
(8:23:23 PM) nwsbot: Local Storm Report by NWS LOT: 2 S Lostant [La Salle Co, IL] trained spotter reports HAIL of quarter size (E1.00 INCH) at 08:15 PM CDT -- near il-18 and i39.



(8:15:55 PM) nwsbot: MKX continues Tornado Warning [tornado: RADAR INDICATED, hail: 1.00 IN] for Kenosha, Racine, Walworth [WI] till 8:30 PM CDT ...AT 815 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO WAS LOCATED NEAR EAGLE LAKE...OR NEAR UNION GROVE...MOVING NORTHEAST AT 65 MPH.



(7:58:40 PM) nwsbot: MKX issues Tornado Warning [tornado: OBSERVED, hail: 1.00 IN] for Kenosha, Racine, Walworth [WI] till 8:30 PM CDT ...AT 757 PM CDT...A TORNADO PRODUCING STORM WAS LOCATED OVER HEBRON...OR NEAR WONDER LAKE...MOVING NORTHEAST AT 65 MPH.
(7:59:17 PM) nwsbot: MKX cancels Severe Thunderstorm Warning for Walworth [WI]
(7:59:17 PM) nwsbot: MKX continues Severe Thunderstorm Warning [wind: 60 MPH, hail: 1.00 IN] for Kenosha, Racine [WI] till 8:15 PM CDT




(7:45:51 PM) nwsbot: LOT expires Tornado Warning for Boone, De Kalb [IL]

(7:45:03 PM) nwsbot: LOT expires Tornado Warning for Boone, Ogle, Winnebago [IL]

(7:41:15 PM) nwsbot: LOT issues Tornado Warning [tornado: OBSERVED, hail: 2.50 IN] for McHenry [IL] till 8:30 PM CDT ...AT 740 PM CDT...A CONFIRMED DANGEROUS TORNADO WAS LOCATED JUST NORTHWEST OF MARENGO AND MOVING NORTHEAST AT 45 MPH.




(7:21:39 PM) nwsbot: LOT continues Tornado Warning [tornado: OBSERVED, hail: 2.75 IN] for Boone, De Kalb [IL] till 7:45 PM CDT ...AT 720 PM CDT...A CONFIRMED LARGE AND EXTREMELY DANGEROUS TORNADO WAS LOCATED NEAR DIXON...AND IS NEARLY STATIONARY.



7:19:37 PM) nwsbot: Local Storm Report by NWS LOT: Crystal Lake [Mchenry Co, IL] trained spotter reports HAIL of nickel size (E0.88 INCH) at 06:58 PM CDT --
(7:19:37 PM) nwsbot: Local Storm Report by NWS LOT: 4 W Kirkland [De Kalb Co, IL] trained spotter reports TORNADO at 07:10 PM CDT -- touchdown between monroe center and fairdale near ogle dekalb county line. damage reported.




(7:17:47 PM) nwsbot: LOT continues Tornado Warning [tornado: RADAR INDICATED, hail: 1.25 IN] for McHenry [IL] till 7:30 PM CDT ...AT 717 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO WAS LOCATED OVER HARVARD...MOVING NORTHEAST AT 40 MPH.

(7:16:58 PM) nwsbot: LOT issues Tornado Warning [tornado: OBSERVED, hail: 2.75 IN] for Boone, De Kalb, McHenry [IL] till 7:45 PM CDT ...AT 716 PM CDT...A CONFIRMED LARGE AND EXTREMELY DANGEROUS TORNADO WAS LOCATED NEAR KIRKLAND...OR 9 MILES SOUTH OF BELVIDERE...MOVING NORTHEAST AT 40 MPH.


(7:16:06 PM) nwsbot: LOT continues Tornado Warning [tornado: RADAR INDICATED, hail: <.75 IN] for Boone, Ogle, Winnebago [IL] till 7:45 PM CDT ...AT 715 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO WAS LOCATED JUST EAST OF STILLMAN VALLEY...MOVING EAST AT 40 MPH.


(7:11:02 PM) nwsbot: LOT continues Tornado Warning [tornado: OBSERVED, hail: 2.75 IN] for Boone, De Kalb, Ogle, Winnebago [IL] till 7:45 PM CDT ...AT 709 PM CDT...A CONFIRMED LARGE AND EXTREMELY DANGEROUS TORNADO WAS LOCATED JUST WEST OF KIRKLAND...OR 11 MILES SOUTHEAST OF ROCKFORD AIRPORT... MOVING NORTHEAST AT 45 MPH. A SECOND TORNADO COULD FORM JUST EAST OF THE CURRENT TORNADO AND COME VERY CLOSE TO THE TOWN OF KIRKLAND.







Severe Thunderstorm Warning for Winnebago and Boone counties has been expired, but continues for Rock and Walworth counties until 6pm.

Severe Thunderstorm Warning for Winnebago and Boone counties until 5:45pm.  Wind gusts to 60 mph and hail one inch in diameter (quarter size) are possible.  This storm is just to the north of Roscoe and moving northeast around 40mph.



Severe Thunderstorm Warning is also in effect for Rock and Walworth counties until 6pm.

5:00pm Update: A Severe Thunderstorm Warning has been issued for Rock and Walworth counties in Southern Wisconsin until 5:30pm.  This storm was just south of Orfordville and moving northeast at 65 mph.  One inch hail and wind gusts over 60 mph are possible.  Heads up Janesville, Beloit, Milton and Brodhead.

3:20pm Update: Skies have cleared to the southwest of Rockford with thunderstorms developing in Lee and Ogle counties.  As of right now, they are not severe, but could produce heavy rainfall.  Right now, there is little forcing occurring in the atmosphere and that will be the case until a cold front in south-central Iowa moves closer.  This doesn't look occur until between 5pm and 7pm.  That will be around the time we'll start to see storm coverage increase.

UPDATE: A Tornado Watch has been expanded to include Winnebago, Boone, McHenry, Ogle, Lee, DeKalb, Green, Rock, and Walworth Counties until 11:00pm this evening.



A Tornado Watch has been issued for Stephenson, Jo Daviess, Carroll and Whiteside counties until 8pm this evening. 

12:30pm Update:  The threat for strong to severe thunderstorms still exists across much of northern and central Illinois with the greatest storm threat extending over much of Illinois and back into extreme eastern Iowa.  While skies are starting to clear a little further south and back into Iowa, there is still some fairly thick cloud cover across southern Wisconsin and northern Illinois.  This will be a great limiting factor in just how unstable the atmosphere can get this afternoon and evening.

Nevertheless, a warm front lies between roughly between Rockford and Rochelle stretching west into south-central Iowa where a strengthening low pressure system is located.  Temperatures are climbing into the low 60's in Rockford, close to 70 degrees in Sterling, but are still in the upper 40's across southern Wisconsin where a stout east wind is keeping the air mass along and just north of the state line stable. 

Instability continues to build south of the warm front, and when combined with the clearing taking place, will be the focus for thunderstorm development later today.  There have already been a few non-severe storms that have been fairly scattered through northern Illinois, and that general trend looks to continue into the early afternoon. 

Storms still look to develop this afternoon, likely between 2pm and 4pm, and depending on the magnitude of clearing, could turn severe rather quickly.  The Storm Prediction Center has highlighted a large portion of northern Illinois in an increased risk for possible tornadoes, and I can't totally disagree with that.  And this is why:  A favorable area for rotating thunderstorms within a storm system is in the area of the 'triple point'.  That's where the low pressure, warm front and cold front meet.  This is where the greatest spin in the atmosphere is located as winds change direction with height.  That location, as of right now, looks to be across northwest Illinois and eastern Iowa.  If thunderstorms develop in that area, the threat for them to rotate increases, and that's how we can get tornadoes. 





11:40am Update: Skies are beginning to clear to the south of Rockford and near the Quad Cities behind a warm front this morning.  Scattered thunderstorms have been moving north and northeast through I-39 late this morning and those are now in northeast Illinois, but those are non-severe.

Thunderstorm development will likely increase across eastern Iowa and quickly race east and northeast into northwest Illinois by 3pm.  Individual storm development this afternoon holds a higher threat for rotating thunderstorms.  A complete analysis will be coming out shortly.






10:00am Update: A little thinning in the cloud cover south of Rockford and near the Quad Cities late this morning will be monitored fairly closely.  There have been a few more thunderstorms firing up south of Amboy in Lee County and along the I-39 corridor.  These have formed near the warm front.

As of right now, thunderstorms are non-severe, but could produce heavy rainfall and pea to nickel sized hail near Amboy.

Thunderstorms producing heavy rain and pea sized hail quickly moved through northern Illinois and southern Wisconsin early Thursday morning.  Now, most of the storm activity has shifted into northeast Illinois and central Wisconsin.  A few widely scattered showers will be possible, but most will remain dry. 

Warm, moist air has been responsible for storm development this morning, but a lid - or cap - on the atmosphere a few thousand feet above kept a lot of the storms from turning severe.

A warm front will pull through northern Illinois and southern Wisconsin later this morning, although it may be delayed just a bit due to the storm activity earlier this morning.  A very warm and humid air mass is found south of the front, and that air mass should be here later this afternoon.  Thunderstorms are expected to develop in Iowa early this afternoon and shift east into the mid-afternoon and evening.  While thunderstorms are likely today, the degree of severity is still in question and that's because of ongoing storms downstate and cloud cover across the Stateline.  If thunderstorms develop this afternoon, hail and damaging winds will be the primary threats, although an isolated tornado will be possible.

As the front shifts east of the Mississippi River today, thunderstorms will quickly race east into northern Illinois.  Best timing for that will be from roughly 2pm/3pm through 9pm, until the cold front passes. 

 Any storms that do develop will be fast moving, not giving you a lot of time to prepare.  Be sure to check back for latest updates throughout the day!