Alert archive / Illinois / Tornado Warnings in 2011

Tornado Warning 52, NWS St. Louis, MO

April 22, 2011Monroe County, Saint Clair County, Illinois

NWS St. Louis, MO issued this tornado warning at Apr 22, 2011, 8:48 PM CDT for Monroe County, Saint Clair County, Illinois. It was in force for 57 min. 4 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
Apr 22, 2011, 8:48 PM CDT (01:48 UTC)
Expired
Apr 22, 2011, 9:45 PM CDT
In force
57 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon

Counties Monroe County, IL, Saint Clair County, IL

The radar

The St Louis radar (KLSX), 74 km from the middle of the area, began a volume at 01:50 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
Apr 22, 8:49 PM CDTHAIL 0.5Waterloo, IL
Apr 22, 8:50 PM CDTTSTM WND DMG1 N Waterloo, ILTREES DOWN
Apr 22, 9:00 PM CDTTSTM WND DMGWaterloo, IL2 AND 4 INCH LIMBS BLOWN DOWN
Apr 22, 9:09 PM CDTHAIL 0.88Smithton, 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.

IssuedProductOfficeLasted
Apr 22, 3:34 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.8 hours before the alert went out and 235 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, Lincoln, IL at 00:00Z on 2011-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 342 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, Lincoln, IL at 00:00Z on 2011-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 351 square meters per square second.1939587897Sfc1 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
342 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
492 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
351 m²/s²
0-3 km storm-relative helicity
346 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

353 
WFUS53 KLSX 230148
TORLSX
ILC133-163-230245-
/O.NEW.KLSX.TO.W.0052.110423T0148Z-110423T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
848 PM CDT FRI APR 22 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN MONROE COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHERN ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 945 PM CDT

* AT 846 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR WATERLOO...AND MOVING EAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WATERLOO...MILLSTADT...FREEBURG...NEW DESIGN...SMITHTON...NEW
  ATHENS...MARISSA...BURKSVILLE...BARR...FLORAVILLE...PADERBORN...
  HECKER...LENZBURG...FAYETTEVILLE AND ST. LIBORY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 3823 8993 3829 9035 3847 9027 3850 8971
      3822 8971
TIME...MOT...LOC 0148Z 273DEG 32KT 3835 9018

$$

BRITT
5 follow-up statements
743 
WWUS53 KLSX 230154
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
854 PM CDT FRI APR 22 2011

ILC133-163-230245-
/O.CON.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
MONROE IL-ST. CLAIR IL-
854 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHERN ST. CLAIR AND
NORTHERN MONROE COUNTIES UNTIL 945 PM CDT...

AT 850 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVERE THUNDERSTORM WITH VERY STRONG ROTATION THAT IS LIKELY 
PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED NEAR 
WATERLOO...MOVING EAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  MILLSTADT...FREEBURG...NEW DESIGN...SMITHTON...NEW ATHENS...
  MARISSA...BARR...FLORAVILLE...PADERBORN...HECKER...LENZBURG...
  FAYETTEVILLE AND ST. LIBORY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 3823 8993 3829 9035 3847 9027 3850 8971
      3822 8971
TIME...MOT...LOC 0153Z 273DEG 28KT 3836 9013

$$

BRITT
610 
WWUS53 KLSX 230207
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
907 PM CDT FRI APR 22 2011

ILC133-163-230245-
/O.CON.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
MONROE IL-ST. CLAIR IL-
907 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHERN ST. CLAIR AND
EAST CENTRAL MONROE COUNTIES UNTIL 945 PM CDT...

AT 903 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVERE THUNDERSTORM WITH VERY STRONG ROTATION THAT IS LIKELY 
PRODUCING A TORNADO.  TREES HAVE BEEN SNAPPED AND BLOWN DOWN 1 MILE 
NORTH OF WATERLOO WITH THIS STORM.  THIS DANGEROUS STORM WAS LOCATED 
NEAR SMITHTON...OR 7 MILES EAST OF WATERLOO...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  FREEBURG...SMITHTON...NEW ATHENS...MARISSA...LENZBURG...
  FAYETTEVILLE AND ST. LIBORY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 3823 8993 3827 9024 3848 9007 3850 8971
      3822 8972
TIME...MOT...LOC 0206Z 269DEG 28KT 3837 9000

$$

BRITT
167 
WWUS53 KLSX 230216
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
916 PM CDT FRI APR 22 2011

ILC133-163-230245-
/O.CON.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
MONROE IL-ST. CLAIR IL-
916 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHERN ST. CLAIR AND
CENTRAL MONROE COUNTIES UNTIL 945 PM CDT...

AT 911 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED NEAR NEW ATHENS...OR NEAR FREEBURG...MOVING EAST AT
35 MPH.  THIS IS AN EXTREMELY DANGEROUS SITUATION...DAMAGE HAS BEEN 
REPORTED WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  MARISSA...LENZBURG AND FAYETTEVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 3823 8993 3827 9024 3848 9007 3850 8971
      3822 8972
TIME...MOT...LOC 0215Z 271DEG 31KT 3836 8988

$$

BRITT
533 
WWUS53 KLSX 230232
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
932 PM CDT FRI APR 22 2011

ILC133-230241-
/O.CAN.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
MONROE IL-
932 PM CDT FRI APR 22 2011

...THE TORNADO WARNING FOR CENTRAL MONROE COUNTY IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

STRONG THUNDERSTORMS ARE STILL MOVING THROUGH THE AREA...AND A 
TORNADO WATCH REMAINS IN EFFECT UNTIL 10 PM CDT.

LAT...LON 3830 8985 3848 8982 3850 8971 3827 8972
TIME...MOT...LOC 0231Z 267DEG 26KT 3839 8972

$$

ILC163-230245-
/O.CON.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
ST. CLAIR IL-
932 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR EAST CENTRAL ST. CLAIR
COUNTY UNTIL 945 PM CDT...

AT 928 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 7 MILES SOUTHWEST OF NEW MEMPHIS...OR 8 MILES SOUTH
OF MASCOUTAH...MOVING EAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME EASTERN ST. CLAIR COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 3830 8985 3848 8982 3850 8971 3827 8972
TIME...MOT...LOC 0231Z 267DEG 26KT 3839 8972

$$

BRITT
338 
WWUS53 KLSX 230237
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
937 PM CDT FRI APR 22 2011

ILC163-230247-
/O.EXP.KLSX.TO.W.0052.000000T0000Z-110423T0245Z/
ST. CLAIR IL-
937 PM CDT FRI APR 22 2011

...THE TORNADO WARNING FOR EAST CENTRAL ST. CLAIR COUNTY WILL EXPIRE
AT 945 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN ST LOUIS.

LAT...LON 3830 8985 3848 8982 3850 8971 3827 8972
TIME...MOT...LOC 0237Z 267DEG 26KT 3839 8966

$$

BRITT

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 22, 7:59 PM CDTTornado WarningLSXMadison, Saint Clair46 min
Apr 22, 8:21 PM CDTTornado WarningLSXMonroe, Saint Clair39 min
Apr 22, 8:33 PM CDTTornado WarningLSXMadison, Saint Clair42 min
Apr 22, 8:55 PM CDTTornado WarningLSXBond, Clinton, Fayette, Madison, Saint Clair50 min
Apr 22, 9:01 PM CDTSevere Thunderstorm WarningLSXFayette, Marion20 min
Apr 22, 9:24 PM CDTTornado WarningLSXClinton, Washington36 min
Apr 22, 9:30 PM CDTFlash Flood WarningLSXMonroe, Saint Clair5 hr
Apr 22, 9:41 PM CDTTornado WarningLSXBond, Fayette, Marion22 min
Apr 22, 9:51 PM CDTFlash Flood WarningLSXClinton, Washington5 hr
Apr 22, 9:59 PM CDTSevere Thunderstorm WarningLSXClinton, Marion, Washington11 min
Apr 22, 10:31 PM CDTTornado WarningLSXMonroe, Randolph, Saint Clair44 min
Apr 22, 10:55 PM CDTFlash Flood WarningLSXMonroe, Randolph6 hr
Apr 22, 11:38 PM CDTRiver Flood WarningLSXBrown25 days
Apr 22, 11:38 PM CDTRiver Flood WarningLSXMorgan, Pike25 days
Apr 22, 11:38 PM CDTRiver Flood WarningLSXPike, Scott31 days
Apr 22, 11:53 PM CDTRiver Flood WarningLSXSaint Clair14 days
Apr 23, 4:23 AM CDTFlash Flood WarningLSXMonroe, Randolph8 hr
Apr 23, 12:29 PM CDTFlash Flood WarningLSXMonroe, Randolph6 hr
Apr 23, 6:22 PM CDTFlash Flood WarningLSXMonroe, Randolph6 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.