Alert archive / Illinois / Tornado Warnings in 2011

Tornado Warning 14, NWS Quad Cities, IA

July 27, 2011Jo Daviess County, Stephenson County, Illinois

NWS Quad Cities, IA issued this tornado warning at Jul 27, 2011, 7:51 PM CDT for Jo Daviess County, Stephenson County, Illinois. It was in force for 39 min. 2 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
Jul 27, 2011, 7:51 PM CDT (00:51 UTC)
Expired
Jul 27, 2011, 8:30 PM CDT
In force
39 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon

Counties Jo Daviess County, IL, Stephenson County, IL

The radar

The Quad Cities radar (KDVN), 111 km from the middle of the area, began a volume at 00:54 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 27, 7:55 PM CDTTORNADO3 Ne Stockton, ILPOSSIBLE TORNADO TOUCHDOWN NEAR JO DAVIES / STEPHENSON COUNTY LINE...RELAYED EMERGENCY MANAGER.
Jul 27, 7:55 PM CDTTORNADO4 Wnw Lena, ILPOSSIBLE TORNADO NEAR TIGER WHIP ROAD.

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.

IssuedProductOfficeLasted
Jul 27, 7:43 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.9 hours before the alert went out and 107 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 00:00Z on 2011-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4556 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 00:00Z on 2011-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 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
4556 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
962 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
316 m²/s²
Significant tornado parameter
3.9
Supercell composite
19.4

Open this sounding in Storm Lab

The text

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

282 
WFUS53 KDVN 280051
TORDVN
ILC085-177-280130-
/O.NEW.KDVN.TO.W.0014.110728T0051Z-110728T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
751 PM CDT WED JUL 27 2011

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN JO DAVIESS COUNTY IN NORTHWEST ILLINOIS...
  NORTHERN STEPHENSON COUNTY IN NORTHWEST ILLINOIS...

* UNTIL 830 PM CDT.

* AT 745 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
  A POSSIBLE TORNADO 3 MILES NORTH OF STOCKTON...OR 19 MILES WEST OF 
  FREEPORT...MOVING EAST AT 20 MPH.

* THE TORNADO WILL BE NEAR...
  KENT AROUND 755 PM CDT...
  WADDAMS GROVE AROUND 800 PM CDT...
  LAKE LEAQUANA STATE PARK AND LENA AROUND 805 PM CDT...
  ELEROY AND WINSLOW AROUND 815 PM CDT...
  MC CONNELL AROUND 820 PM CDT...
  BUENA VISTA...RED OAK AND DAMASCUS AROUND 825 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE IN A TORNADO IS IN A BASEMENT OR INTERIOR ROOM
OR HALLWAY ON THE LOWEST FLOOR OF A BUILDING.

PLEASE REPORT ANY SEVERE WEATHER OR DAMAGE TO YOUR LOCAL LAW
ENFORCEMENT AGENCY FOR RELAY TO THE NATIONAL WEATHER SERVICE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

&&

LAT...LON 4250 8992 4250 8941 4229 8940 4230 9007
      4248 9009
TIME...MOT...LOC 0050Z 266DEG 19KT 4240 8995

$$

LE
2 follow-up statements
270 
WWUS53 KDVN 280107
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
807 PM CDT WED JUL 27 2011

ILC085-280115-
/O.CAN.KDVN.TO.W.0014.000000T0000Z-110728T0130Z/
JO DAVIESS IL-
807 PM CDT WED JUL 27 2011

...THE TORNADO WARNING FOR NORTHEASTERN JO DAVIESS COUNTY IS
CANCELLED...

THE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING A TORNADO HAS MOVED 
EAST OUT OF THE WARNED AREA. THEREFORE THIS TORNADO WARNING HAS BEEN 
CANCELLED.  HOWEVER...ANOTHER TORNADO WARNING WITH A POSSIBLE 
TORNADO REMAINS IN EFFECT FOR ANOTHER PORTION OF THE COUNTY.  

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

LAT...LON 4230 8992 4250 8992 4250 8941 4229 8940
TIME...MOT...LOC 0105Z 266DEG 19KT 4241 8984

$$

ILC177-280130-
/O.CON.KDVN.TO.W.0014.000000T0000Z-110728T0130Z/
STEPHENSON IL-
807 PM CDT WED JUL 27 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR NORTHERN
STEPHENSON COUNTY...

AT 802 PM CDT...TRAINED SPOTTERS AND DOPPLER RADAR INDICATED A 
TORNADO.  THIS TORNADO WAS LOCATED APPROXIMATELY NEAR WADDAMS 
GROVE...OR 14 MILES NORTHWEST OF FREEPORT...MOVING EAST AT 20 MPH.

THE TORNADO WILL BE NEAR...
  ELEROY AND WINSLOW AROUND 815 PM CDT...
  MC CONNELL AROUND 820 PM CDT...
  DAMASCUS AROUND 825 PM CDT...
  BUENA VISTA...RED OAK...CEDARVILLE AND ORANGEVILLE AROUND 830 PM
  CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT ANY SEVERE WEATHER OR DAMAGE TO YOUR LOCAL LAW
ENFORCEMENT AGENCY FOR RELAY TO THE NATIONAL WEATHER SERVICE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

&&

LAT...LON 4230 8992 4250 8992 4250 8941 4229 8940
TIME...MOT...LOC 0105Z 266DEG 19KT 4241 8984

$$

LE
365 
WWUS53 KDVN 280130
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
830 PM CDT WED JUL 27 2011

ILC177-280140-
/O.EXP.KDVN.TO.W.0014.000000T0000Z-110728T0130Z/
STEPHENSON IL-
830 PM CDT WED JUL 27 2011

...THE TORNADO WARNING FOR NORTHERN STEPHENSON COUNTY HAS EXPIRED...

THE SEVERE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING A TORNADO HAS 
WEAKENED...AND A TORNADO IS NO LONGER EXPECTED. THEREFORE THE 
TORNADO WARNING HAS BEEN ALLOWED TO EXPIRE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

LAT...LON 4230 8992 4250 8992 4250 8941 4229 8940
TIME...MOT...LOC 0107Z 266DEG 19KT 4241 8983

$$

LE

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 27, 7:10 PM CDTFlash Flood WarningDVNJo Daviess9 hr
Jul 27, 7:35 PM CDTTornado WarningDVNJo Daviess40 min
Jul 27, 8:40 PM CDTFlash Flood WarningDVNStephenson8 hr
Jul 27, 9:16 PM CDTTornado WarningDVNCarroll, Jo Daviess31 min
Jul 27, 11:55 PM CDTFlash Flood WarningDVNCarroll4 hr
Jul 28, 12:50 AM CDTSpecial Weather StatementDVNCarroll, Jo Daviess, Stephenson55 min
Jul 28, 4:10 AM CDTAreal Flood WarningDVNCarroll, Jo Daviess, Stephenson12 hr
Jul 28, 9:40 AM CDTSpecial Weather StatementDVNRock Island, Whiteside50 min
Jul 28, 10:15 AM CDTRiver Flood WarningDVNJo Daviess6 hr
Jul 28, 10:15 AM CDTRiver Flood WarningDVNCarroll, Jo Daviess6 hr
Jul 28, 10:15 AM CDTRiver Flood WarningDVNStephenson43 hr
Jul 28, 12:03 PM CDTHeat AdvisoryDVNHancock, Henderson, McDonough, Mercer, Warren10 hr
Jul 28, 3:39 PM CDTAreal Flood WarningDVNCarroll, Jo Daviess, Stephenson6 hr

Nearby

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