Alert archive / Illinois / Tornado Warnings in 2021

Tornado Warning 22, NWS Chicago, IL

July 7, 2021Winnebago County, Illinois

NWS Chicago, IL issued this tornado warning at Jul 7, 2021, 1:16 PM CDT for Winnebago County, Illinois. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 7, 2021, 1:16 PM CDT (18:16 UTC)
Expired
Jul 7, 2021, 1:51 PM CDT
In force
35 min
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Winnebago County, IL

The radar

The Milwaukee radar (KMKX), 73 km from the middle of the area, began a volume at 18:17 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jul 7, 1:35 PM CDTFUNNEL CLOUDRockton, ILLOCAL BROADCAST METEOROLOGIST RELAYED SEVERAL HIGH-BASED FUNNELS WERE OBSERVED VIEWED FROM IL-2 NEAR ROCKTON AS WELL AS ONE 1/4 OF THE WAY DOWN TO THE GROUND NEAR SOUTH BELOIT. NO CONTACT WITH THE GROUND WAS SEEN WITH ANY FUNNEL. ALSO, 40-50 MPH WIND GUSTS WER

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 6.3 hours before the alert went out and 149 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2021-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 119 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2021-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
119 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
1359 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

650 
WFUS53 KLOT 071816
TORLOT
ILC201-071900-
/O.NEW.KLOT.TO.W.0022.210707T1816Z-210707T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Chicago/Romeoville
116 PM CDT Wed Jul 7 2021

The National Weather Service in Chicago has issued a

* Tornado Warning for...
  Northern Winnebago County in north central Illinois...

* Until 200 PM CDT.
    
* At 115 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Rockton, moving east at 25 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  South Beloit and Rockton around 130 PM CDT.
  Machesney Park and Roscoe around 135 PM CDT.

Including the following interstate...
 I-90 between mile markers 1 and 9.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4249 8894 4237 8894 4239 8931 4250 8931
TIME...MOT...LOC 1815Z 269DEG 23KT 4246 8918 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

MDB
2 follow-up statements
037 
WWUS53 KLOT 071825
SVSLOT

Severe Weather Statement
National Weather Service Chicago/Romeoville
125 PM CDT Wed Jul 7 2021

ILC201-071900-
/O.CON.KLOT.TO.W.0022.000000T0000Z-210707T1900Z/
Winnebago IL-
125 PM CDT Wed Jul 7 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 200 PM CDT FOR
NORTHEASTERN WINNEBAGO COUNTY...
    
At 125 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Rockton, moving east at 25 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Rockton around 130 PM CDT.
  Machesney Park and South Beloit around 135 PM CDT.

Other locations in the path of this tornadic thunderstorm include
Roscoe.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4249 8894 4237 8894 4239 8922 4250 8923
TIME...MOT...LOC 1825Z 267DEG 22KT 4247 8912 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

MDB
140 
WWUS53 KLOT 071851
SVSLOT

Severe Weather Statement
National Weather Service Chicago/Romeoville
151 PM CDT Wed Jul 7 2021

ILC201-071858-
/O.CAN.KLOT.TO.W.0022.000000T0000Z-210707T1900Z/
Winnebago IL-
151 PM CDT Wed Jul 7 2021

...THE TORNADO WARNING FOR NORTHEASTERN WINNEBAGO COUNTY IS
CANCELLED...
    
The tornadic thunderstorm which prompted the warning has weakened. 
However thunderstorms with heavy rain continue from Rockton to Loves 
Park.

LAT...LON 4249 8894 4237 8894 4239 8922 4250 8923
TIME...MOT...LOC 1847Z 269DEG 23KT 4247 8891 

$$

MDB

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 7, 12:26 PM CDTSpecial Weather StatementLOTKankakee94 min
Jul 7, 4:28 PM CDTMarine Dense Fog AdvisoryLOT6 hr

Nearby

Tornado Warnings in Illinois, 2021Every tornado warning in 2021Tornadoes in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.