Alert archive / Illinois / Tornado Warnings in 2011

Tornado Warning 21, NWS Chicago, IL

June 21, 20117 counties in Illinois

NWS Chicago, IL issued this tornado warning at Jun 21, 2011, 7:57 PM CDT for 7 counties in Illinois. It was in force for 63 min. 27 reports 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: Jun 21, 2011, 7:57 PM CDT (00:57 UTC)
Expired: Jun 21, 2011, 9:00 PM CDT
In force: 63 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon

Counties Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kendall County, IL, Will County, IL

The radar

The Chicago radar (KLOT), 26 km from the middle of the area, began a volume at 00:57 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

Time	Report	Where	Remark
Jun 21, 8:05 PM CDT	FUNNEL CLOUD	4 Nnw Sugar Grove, IL	RT 47 AND I88
Jun 21, 8:10 PM CDT	TSTM WND GST 60	Romeoville, IL	NORMANTOWN RD AND HUDSON
Jun 21, 8:11 PM CDT	TSTM WND GST 65	Aurora, IL	ONE BLOCK SOUTH OF FOUR SEASONS BLVD AND VICTORIA CIRCLE.
Jun 21, 8:11 PM CDT	TSTM WND GST 65	Aurora, IL	ONE BLOCK SOUTH OF FOUR SEASONS BLVD AND VICTORIA CIRCLE.
Jun 21, 8:15 PM CDT	TSTM WND GST 65	Joliet, IL	CATON FARM AND ESSINGTON
Jun 21, 8:17 PM CDT	TSTM WND GST 51	Romeoville, IL
Jun 21, 8:19 PM CDT	TSTM WND GST 50	Bolingbrook, IL	LILY CACHE AND RT 53
Jun 21, 8:25 PM CDT	TSTM WND GST 58	4 Wsw Lisle, IL
Jun 21, 8:28 PM CDT	TSTM WND GST 75	Wheaton, IL	ROOSELVELT AND COUNTY FARM RD. TRANSFORMERS EXPLODING
Jun 21, 8:30 PM CDT	TSTM WND DMG	Westmont, IL	15 INCH DIAMETER TREE SPLIT DOWN THE MIDDLE. 6 INCH DIAMETER BRANCH BROKEN OFF.
Jun 21, 8:30 PM CDT	TSTM WND GST 60	Romeoville, IL	MEASURED AT NWS OFFICE.
Jun 21, 8:30 PM CDT	TSTM WND GST 66	Romeoville, IL	LOT AWOS MEASUREMENT.
Jun 21, 8:30 PM CDT	TSTM WND GST 70	Naperville, IL	SMALL TREE LIMB DAMAGE.
Jun 21, 8:30 PM CDT	TSTM WND GST 71	5 W Bolingbrook, IL
Jun 21, 8:31 PM CDT	TORNADO	2 S Downers Grove, IL	STORM SURVEY CONFIRMED AN EF-1 TORNADO TOUCHED DOWN NEAR SUNNYDALE PARK AND LIFTED NEAR 55TH AND MAIN IN DOWNERS GROVE. PATH WIDTH WAS APPROXIMATELY 200 YARDS AND PATH LENGTH APPROXIMATELY 2.1 MILES.
Jun 21, 8:35 PM CDT	TSTM WND GST 60	Bolingbrook, IL	SMALL TREES DOWN
Jun 21, 8:35 PM CDT	TSTM WND GST 60	Bolingbrook, IL	SMALL TRESS DOWN
Jun 21, 8:37 PM CDT	TSTM WND DMG	Oak Brook, IL	NUMEROUS BRANCHES DOWN AND POWER OUTAGES
Jun 21, 8:37 PM CDT	TSTM WND GST 59	4 Sse Carol Stream, IL
Jun 21, 8:41 PM CDT	TSTM WND DMG	Lombard, IL	LARGE TREE FALLEN ON RT 53 ONE MILE NORTH OF ROOSEVELT ROAD. TREE IS COVERING THE ENTIRE LANE ON THE NORTH BOUND SIDE.
Jun 21, 8:41 PM CDT	TSTM WND GST 60	West Chicago, IL
Jun 21, 8:41 PM CDT	TSTM WND GST 62	Wheaton, IL	DUPAGE COUNTY EOC
Jun 21, 8:45 PM CDT	TSTM WND DMG	Downers Grove, IL	DELAYED REPORT. NEAR THE INTERSECTION OF FAIRVIEW AND GIERZ A TREE 14 INCHES IN DIAMETER UPROOTED ON THE PARKWAY.
Jun 21, 8:45 PM CDT	TSTM WND DMG	Westmont, IL	DELAYED REPORT. NEAR 63RD STREET AND CASS AVENUE. THE TOP OF A MAPLE TREE BROKE OFF. THE TRUNK WAS 6 TO 8 INCHES IN DIAMETER.
Jun 21, 8:46 PM CDT	TSTM WND GST 65	Downers Grove, IL	ESTIMATED 65 MPH WIND GUSTS CAUSED STRUCTURAL DAMAGE TO ROOFS AND DOWNED 18 INCH LIMBS FROM TREES NEAR THE 59TH AND FAIRVIEW INTERSECTION TO THE 63RD AND MAIN STREET INTERSECTION.
Jun 21, 9:00 PM CDT	TSTM WND DMG	Bolingbrook, IL	SIDEWALL OF ALUMINUM SHED BLOWN IN
Jun 21, 9:00 PM CDT	TSTM WND GST 60	1 E Elgin, IL

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 21, 5:42 PM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.0 hours before the alert went out and 177 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3122 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 829 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 147 m²/s²
0-3 km storm-relative helicity: 207 m²/s²
Significant tornado parameter: 3.5
Supercell composite: 15.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

617 
WFUS53 KLOT 220057
TORLOT
ILC031-037-043-063-089-093-197-220200-
/O.NEW.KLOT.TO.W.0021.110622T0057Z-110622T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
757 PM CDT TUE JUN 21 2011

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWEST COOK COUNTY...
  EASTERN DE KALB COUNTY...
  DUPAGE COUNTY...
  GRUNDY COUNTY...
  KANE COUNTY...
  KENDALL COUNTY...
  WESTERN WILL COUNTY...

* UNTIL 900 PM CDT

* AT 753 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE SQUALL LINE CAPABLE OF PRODUCING BRIEF RAIN-WRAPPED
  TORNADOES IN ADDITION TO WIDESPREAD STRAIGHT LINE WIND DAMAGE.
  THESE DANGEROUS STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 5
  MILES SOUTH OF CORTLAND TO LITTLE ROCK TO 6 MILES EAST OF NEWARK TO
  7 MILES SOUTHWEST OF MAZON...AND MOVING NORTHEAST AT 45 MPH.

* THESE STORMS WILL BE NEAR...
  SYCAMORE...SUGAR GROVE...MORRIS AND MAZON AROUND 805 PM.
  OSWEGO...MONTGOMERY AND ELBURN AROUND 810 PM.
  NORTH AURORA AND AURORA AROUND 815 PM.
  MINOOKA...GENEVA...COAL CITY AND BATAVIA AROUND 820 PM.
  ST. CHARLES AND SHOREWOOD AROUND 825 PM.

OTHER LOCATIONS IMPACTED BY THESE TORNADIC THUNDERSTORMS INCLUDE
BOULDER HILL...BURLINGTON...CARBON HILL...PINGREE GROVE...SOUTH
ELGIN...CRYSTAL LAWNS...CREST HILL...PRESTON HEIGHTS...GLENDALE
HEIGHTS AND GLENBARD SOUTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS TORNADO WARNING REPLACES THE SEVERE THUNDERSTORM WARNING THAT
WAS IN EFFECT FOR THE SAME AREA. GO TO A BASEMENT OR SMALL INTERIOR
ROOM ON THE LOWEST FLOOR!

&&

LAT...LON 4202 8807 4184 8793 4144 8800 4111 8858
      4151 8854 4163 8860 4189 8881 4215 8852
TIME...MOT...LOC 0056Z 235DEG 39KT 4187 8870 4174 8853
          4157 8844 4121 8852

$$

IZZI

4 follow-up statements

613 
WWUS53 KLOT 220115
SVSLOT

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
815 PM CDT TUE JUN 21 2011

ILC031-037-043-063-089-093-197-220200-
/O.CON.KLOT.TO.W.0021.000000T0000Z-110622T0200Z/
KANE IL-KENDALL IL-WILL IL-GRUNDY IL-DE KALB IL-DUPAGE IL-COOK IL-
815 PM CDT TUE JUN 21 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL COOK...
DUPAGE...SOUTHEASTERN DE KALB...GRUNDY...NORTHWESTERN WILL...KENDALL
AND KANE COUNTIES UNTIL 900 PM CDT...

AT 811 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE SQUALL LINE CAPABLE OF PRODUCING DAMAGING STRAIGHT LINE WINDS
AND BRIEF RAIN-WRAPPED TORNADOES.  THESE DANGEROUS STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM MAPLE PARK TO NORTH AURORA TO
OSWEGO TO COAL CITY...MOVING NORTHEAST AT 45 MPH.

THESE DANGEROUS STORMS WILL BE NEAR...
  WEST CHICAGO...WARRENVILLE...ST. CHARLES AND SHOREWOOD AROUND 820
  PM CDT.
  WINFIELD AND WAYNE AROUND 825 PM CDT.
  GILBERTS...WOODRIDGE...WHEATON AND ROMEOVILLE AROUND 830 PM CDT.
  DARIEN...YORK CENTER...WESTMONT AND STREAMWOOD AROUND 835 PM CDT.
  VILLA PARK AROUND 840 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS LINE OF TORNADO PRODUCING STORMS
INCLUDE PINGREE GROVE...SOUTH ELGIN...CRYSTAL LAWNS...GLENBARD
SOUTH...CREST HILL...PRESTON HEIGHTS...GLENDALE HEIGHTS...FAIRMONT...
BLOOMINGDALE AND WILLOWBROOK.

LAT...LON 4202 8807 4184 8793 4144 8800 4111 8858
      4151 8854 4163 8860 4189 8881 4215 8852
TIME...MOT...LOC 0115Z 235DEG 39KT 4198 8849 4185 8832
          4168 8823 4132 8831

$$

BIRK

166 
WWUS53 KLOT 220127
SVSLOT

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
827 PM CDT TUE JUN 21 2011

ILC031-037-043-063-089-093-197-220200-
/O.CON.KLOT.TO.W.0021.000000T0000Z-110622T0200Z/
KANE IL-KENDALL IL-WILL IL-GRUNDY IL-DE KALB IL-DUPAGE IL-COOK IL-
827 PM CDT TUE JUN 21 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL COOK...
DUPAGE...EAST CENTRAL DE KALB...NORTHEASTERN GRUNDY...NORTHWESTERN
WILL...KENDALL AND KANE COUNTIES UNTIL 900 PM CDT...

AT 824 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE SQUALL LINE CAPABLE OF PRODUCING DAMAGING STRAIGHT LINE WINDS
AND BRIEF RAIN-WRAPPED TORNADOES.  THESE DANGEROUS STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM 5 MILES SOUTHWEST OF GILBERTS TO
DUPAGE AIRPORT TO NAPERVILLE TO ROCKDALE...MOVING NORTHEAST AT 45
MPH.

THESE DANGEROUS STORMS WILL BE NEAR...
  WOODRIDGE...WHEATON...STREAMWOOD AND LEMONT AROUND 835 PM CDT.
  YORK CENTER...WESTMONT...ROSELLE AND MEDINAH AROUND 840 PM CDT.
  VILLA PARK AND OAK BROOK AROUND 845 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS LINE OF TORNADO PRODUCING STORMS
INCLUDE GLENDALE HEIGHTS...GLENBARD SOUTH...WILLOWBROOK...
BLOOMINGDALE AND OAKBROOK TERRACE.

LAT...LON 4130 8826 4164 8856 4196 8873 4215 8852
      4202 8807 4184 8793 4144 8800
TIME...MOT...LOC 0127Z 230DEG 37KT 4206 8839 4193 8823
          4176 8814 4153 8806

$$

BIRK

897 
WWUS53 KLOT 220139
SVSLOT

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
839 PM CDT TUE JUN 21 2011

ILC037-063-093-220149-
/O.CAN.KLOT.TO.W.0021.000000T0000Z-110622T0200Z/
KENDALL IL-GRUNDY IL-DE KALB IL-
839 PM CDT TUE JUN 21 2011

...THE TORNADO WARNING FOR EAST CENTRAL DE KALB...NORTHEASTERN GRUNDY
AND KENDALL COUNTIES IS CANCELLED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE MOVED 
OUT OF THE WARNED AREA.

LAT...LON 4144 8820 4173 8825 4206 8854 4215 8852
      4202 8807 4184 8793 4144 8800
TIME...MOT...LOC 0139Z 230DEG 37KT 4214 8835 4195 8818
          4184 8801 4161 8793

$$

ILC031-043-089-197-220200-
/O.CON.KLOT.TO.W.0021.000000T0000Z-110622T0200Z/
KANE IL-WILL IL-DUPAGE IL-COOK IL-
839 PM CDT TUE JUN 21 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL COOK...
DUPAGE...NORTHWESTERN WILL AND NORTHERN KANE COUNTIES UNTIL 900 PM
CDT...

AT 834 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE SQUALL LINE CAPABLE OF PRODUCING DAMAGING STRAIGHT LINE WINDS
AND BRIEF RAIN-WRAPPED TORNADOES.  THESE DANGEROUS STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM GILBERTS TO DUPAGE AIRPORT TO
LISLE TO LOCKPORT...MOVING NORTHEAST AT 45 MPH.

THESE DANGEROUS STORMS WILL BE NEAR...
  VILLA PARK...STREAMWOOD...ROSELLE AND OAK BROOK AROUND 845 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS LINE OF TORNADO PRODUCING STORMS
INCLUDE OAKBROOK TERRACE AND BLOOMINGDALE.

LAT...LON 4144 8820 4173 8825 4206 8854 4215 8852
      4202 8807 4184 8793 4144 8800
TIME...MOT...LOC 0139Z 230DEG 37KT 4214 8835 4195 8818
          4184 8801 4161 8793

$$

BIRK

566 
WWUS53 KLOT 220152
SVSLOT

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
852 PM CDT TUE JUN 21 2011

ILC031-043-089-197-220202-
/O.EXP.KLOT.TO.W.0021.000000T0000Z-110622T0200Z/
KANE IL-WILL IL-DUPAGE IL-COOK IL-
852 PM CDT TUE JUN 21 2011

...THE TORNADO WARNING FOR WEST CENTRAL COOK...DUPAGE...NORTHWESTERN
WILL AND NORTHERN KANE COUNTIES WILL EXPIRE AT 900 PM CDT...

THE LINE OF STORMS WHICH PROMPTED THE WARNING ARE MOVING OUT OF THE
WARNED AREA...HOWEVER GUSTY WINDS AND HEAVY RAIN ARE STILL POSSIBLE
WITH THESE THUNDERSTORMS.

LAT...LON 4144 8820 4173 8825 4206 8854 4215 8852
      4202 8807 4184 8793 4144 8800
TIME...MOT...LOC 0152Z 230DEG 37KT 4223 8821 4203 8804
          4192 8787 4169 8779

$$

BIRK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 21, 7:17 PM CDT	Special Weather Statement	LOT	Ford, Iroquois, Livingston
Jun 21, 7:19 PM CDT	Special Marine Warning	LOT		3 hr
Jun 21, 7:22 PM CDT	Severe Thunderstorm Warning	LOT	McHenry	23 min
Jun 21, 7:23 PM CDT	Special Weather Statement	LOT	Ford, Iroquois, Kankakee, Will	67 min
Jun 21, 7:27 PM CDT	Tornado Warning	LOT	LaSalle, Livingston	33 min
Jun 21, 7:31 PM CDT	Severe Thunderstorm Warning	LOT	DeKalb, DuPage, Grundy, Kane, Kendall, LaSalle and 2 more	37 min
Jun 21, 8:01 PM CDT	Areal Flood Advisory	LOT	LaSalle	6 hr
Jun 21, 8:22 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kane, Lake, McHenry, Will	53 min
Jun 21, 8:38 PM CDT	Tornado Warning	LOT	Cook, DuPage, Lake	52 min
Jun 21, 9:19 PM CDT	Areal Flood Advisory	LOT	DeKalb, Grundy, Kane, Kendall, LaSalle	6 hr
Jun 22, 9:58 AM CDT	Small Craft Advisory	LOT		12 hr
Jun 22, 11:19 AM CDT	River Flood Advisory	LOT	LaSalle	17 hr

Nearby

Tornado Warnings in Illinois, 2011 Every tornado warning in 2011 Tornadoes in 2011

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.