Alert archive / Missouri / Tornado Warnings in 2011

Tornado Warning 50, NWS St. Louis, MO

April 22, 2011Jefferson County, Saint Louis County, Missouri; Monroe County, Saint Clair County, Illinois

NWS St. Louis, MO issued this tornado warning at Apr 22, 2011, 8:21 PM CDT for Jefferson County, Saint Louis County, Missouri; Monroe County, Saint Clair County, Illinois. It was in force for 39 min. 7 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, 8:21 PM CDT (01:21 UTC)
Expired
Apr 22, 2011, 9:00 PM CDT
In force
39 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon

Counties Monroe County, IL, Saint Clair County, IL, Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 50 km from the middle of the area, began a volume at 01:25 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, 8:25 PM CDTHAIL 0.5High Ridge, MO
Apr 22, 8:30 PM CDTHAIL 0.88Oakville, MO
Apr 22, 8:42 PM CDTHAIL 0.75Columbia, IL
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, 1.4 hours before the alert went out and 244 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.

396 
WFUS53 KLSX 230121
TORLSX
ILC133-163-MOC099-189-230200-
/O.NEW.KLSX.TO.W.0050.110423T0121Z-110423T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
821 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...
  ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...
  NORTHEASTERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  SOUTH CENTRAL ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 900 PM CDT

* AT 816 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR HOUSE SPRINGS...OR NEAR ANTONIA...AND MOVING
  EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  BARNHART...PEVELY...ARNOLD...OAKVILLE...MEHLVILLE...COLUMBIA...
  DUPO...WATERLOO...MILLSTADT...BELLEVILLE...SWANSEA...FREEBURG...
  SHILOH...SCOTT AFB...VALMEYER...FOUNTAIN...NEW DESIGN...SMITHTON...
  NEW ATHENS AND KIMMSWICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

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

&&

LAT...LON 3830 9058 3846 9058 3861 8982 3822 8981
TIME...MOT...LOC 0121Z 267DEG 42KT 3837 9046

$$

BRITT
3 follow-up statements
193 
WWUS53 KLSX 230127
SVSLSX

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

ILC133-163-MOC099-189-230200-
/O.CON.KLSX.TO.W.0050.000000T0000Z-110423T0200Z/
MONROE IL-ST. CLAIR IL-JEFFERSON MO-ST. LOUIS MO-
827 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTH CENTRAL ST. LOUIS...
NORTHEASTERN JEFFERSON...ST. CLAIR AND NORTHERN MONROE COUNTIES UNTIL
900 PM CDT...

AT 825 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED NEAR ANTONIA...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  PEVELY...ARNOLD...MEHLVILLE...OAKVILLE...COLUMBIA...DUPO...
  WATERLOO...MILLSTADT...FREEBURG...BELLEVILLE...SWANSEA...SHILOH...
  SCOTT AFB...O'FALLON...VALMEYER...FOUNTAIN...NEW DESIGN...
  SMITHTON...NEW ATHENS AND KIMMSWICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

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

&&

LAT...LON 3830 9055 3849 9045 3861 8982 3822 8981
TIME...MOT...LOC 0128Z 273DEG 32KT 3836 9041

$$

BRITT
942 
WWUS53 KLSX 230136
SVSLSX

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

MOC099-189-230145-
/O.CAN.KLSX.TO.W.0050.000000T0000Z-110423T0200Z/
JEFFERSON MO-ST. LOUIS MO-
836 PM CDT FRI APR 22 2011

...THE TORNADO WARNING FOR SOUTH CENTRAL ST. LOUIS AND NORTHEASTERN
JEFFERSON COUNTIES IS CANCELLED...

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

LAT...LON 3829 9038 3837 9036 3842 9031 3846 9028
      3861 8982 3822 8981
TIME...MOT...LOC 0135Z 273DEG 32KT 3836 9033

$$

ILC133-163-230200-
/O.CON.KLSX.TO.W.0050.000000T0000Z-110423T0200Z/
MONROE IL-ST. CLAIR IL-
836 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR ST. CLAIR AND NORTHERN
MONROE COUNTIES UNTIL 900 PM CDT...

AT 833 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  ROTATION IS 
INCREASING ON RADAR AND THE TORNADO MAY BE RAIN WRAPPED AND 
DIFFICULT TO SEE AT NIGHT.  THIS DANGEROUS STORM WAS LOCATED NEAR 
BARNHART...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  COLUMBIA...WATERLOO...MILLSTADT...FREEBURG...BELLEVILLE...
  SWANSEA...SHILOH...SCOTT AFB...VALMEYER...FOUNTAIN...NEW DESIGN...
  SMITHTON...NEW ATHENS...FOSTER POND...NEW HANDOVER...WARTBURG...
  BURKSVILLE...BARR...FLORAVILLE AND PADERBORN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

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 3829 9038 3837 9036 3842 9031 3846 9028
      3861 8982 3822 8981
TIME...MOT...LOC 0135Z 273DEG 32KT 3836 9033

$$

BRITT
117 
WWUS53 KLSX 230144
SVSLSX

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

ILC133-163-230200-
/O.CON.KLSX.TO.W.0050.000000T0000Z-110423T0200Z/
MONROE IL-ST. CLAIR IL-
844 PM CDT FRI APR 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR ST. CLAIR AND NORTHERN
MONROE COUNTIES UNTIL 900 PM CDT...

AT 842 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED NEAR FOUNTAIN...OR 5 MILES WEST OF WATERLOO...
MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  WATERLOO...MILLSTADT...FREEBURG...BELLEVILLE...SWANSEA...SHILOH...
  SCOTT AFB...NEW DESIGN...SMITHTON...NEW ATHENS...WARTBURG...
  BURKSVILLE...BARR...FLORAVILLE...PADERBORN...HECKER AND LENZBURG.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

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 3829 9038 3837 9036 3842 9031 3846 9028
      3861 8982 3822 8981
TIME...MOT...LOC 0144Z 273DEG 32KT 3836 9023

$$

BRITT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 22, 7:11 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade, Saint Charles, Warren49 min
Apr 22, 7:20 PM CDTTornado WarningLSXFranklin, Gasconade, Saint Charles40 min
Apr 22, 7:36 PM CDTTornado WarningLSXSaint Charles, Saint Louis39 min
Apr 22, 7:44 PM CDTTornado WarningLSXReynolds16 min
Apr 22, 7:56 PM CDTTornado WarningLSXFranklin, Jefferson, Saint Louis42 min
Apr 22, 7:59 PM CDTTornado WarningLSXSaint Louis, City of Saint Louis46 min
Apr 22, 9:00 PM CDTFlash Flood WarningLSXFranklin, Jefferson, Saint Louis5 hr
Apr 22, 10:18 PM CDTRiver Flood WarningLSXJefferson8 days
Apr 22, 10:55 PM CDTFlash Flood WarningLSXCrawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more6 hr
Apr 22, 11:10 PM CDTRiver Flood WarningLSXLewis25 hr
Apr 22, 11:12 PM CDTTornado WarningLSXIron, Madison, Sainte Genevieve, Saint Francois37 min
Apr 22, 11:53 PM CDTRiver Flood WarningLSXSaint Louis, City of Saint Louis14 days
Apr 23, 1:21 AM CDTSevere Thunderstorm WarningLSXIron, Madison, Reynolds, Sainte Genevieve, Saint Francois30 min
Apr 23, 1:47 AM CDTRiver Flood WarningLSXGasconade, Montgomery9 days
Apr 23, 4:23 AM CDTFlash Flood WarningLSXCrawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more8 hr
Apr 23, 6:45 AM CDTRiver Flood WarningLSXLewis39 hr
Apr 23, 12:29 PM CDTFlash Flood WarningLSXCrawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more6 hr
Apr 23, 4:59 PM CDTSevere Thunderstorm WarningLSXIron, Reynolds46 min
Apr 23, 5:27 PM CDTSevere Thunderstorm WarningLSXCrawford, Washington48 min
Apr 23, 5:41 PM CDTSevere Thunderstorm WarningLSXCrawford, Franklin, Jefferson, Washington33 min
Apr 23, 6:22 PM CDTFlash Flood WarningLSXCrawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more6 hr
Apr 22, 8:33 PM CDTTornado WarningLSXMadison, Saint Clair42 min
Apr 22, 8:48 PM CDTTornado WarningLSXMonroe, Saint Clair57 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, 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

Nearby

Tornado Warnings in Missouri, 2011Tornado 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.