Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 81, NWS St. Louis, MO

April 19, 2011Monroe County, Saint Clair County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 19, 2011, 6:56 AM CDT for Monroe County, Saint Clair County, Illinois. It was in force for 49 min. 3 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 19, 2011, 6:56 AM CDT (11:56 UTC)
Expired
Apr 19, 2011, 7:45 AM CDT
In force
49 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
2.75 in
Wind
50.0 mph

Counties Monroe County, IL, Saint Clair County, IL

The radar

The St Louis radar (KLSX), 75 km from the middle of the area, began a volume at 11:56 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 19, 7:03 AM CDTHAIL 1.751 Sw New Handover, IL
Apr 19, 7:04 AM CDTHAIL 1.75Waterloo, IL
Apr 19, 7:17 AM CDTHAIL 0.25Scott Afb, 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 19, 3:11 AM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 11.9 hours before the alert went out and 233 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 2011-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2011-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 194 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1035 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
194 m²/s²
0-3 km storm-relative helicity
347 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

027 
WUUS53 KLSX 191156
SVRLSX
ILC133-163-191245-
/O.NEW.KLSX.SV.W.0081.110419T1156Z-110419T1245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
656 AM CDT TUE APR 19 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 745 AM CDT

* AT 651 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DESTRUCTIVE HAIL UP
  TO BASEBALL SIZE.  THIS STORM WAS LOCATED NEAR WATERLOO...AND   
  MOVING EAST AT 45 MPH.  BETWEEN 640 AND 650 AM...TWO INCH DIAMETER 
  FELL IN VALMEYER WITH THIS STORM.

* LOCATIONS IMPACTED INCLUDE...
  MILLSTADT...FREEBURG...SCOTT AFB...MASCOUTAH...SMITHTON...NEW
  ATHENS...MARISSA...BARR...FLORAVILLE...PADERBORN...HECKER...
  LENZBURG AND FAYETTEVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR LARGE DESTRUCTIVE HAIL CAPABLE OF PRODUCING
SIGNIFICANT DAMAGE. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 3822 8972 3823 9035 3844 9029 3858 8971
TIME...MOT...LOC 1154Z 257DEG 38KT 3833 9014
WIND...HAIL <50MPH 2.75IN

$$

BRITT
3 follow-up statements
539 
WWUS53 KLSX 191213
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
713 AM CDT TUE APR 19 2011

ILC133-163-191245-
/O.CON.KLSX.SV.W.0081.000000T0000Z-110419T1245Z/
MONROE IL-ST. CLAIR IL-
713 AM CDT TUE APR 19 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHERN ST.
CLAIR AND NORTHEASTERN MONROE COUNTIES UNTIL 745 AM CDT...

AT 711 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL.  THIS 
STORM WAS LOCATED NEAR FREEBURG...MOVING EAST AT 40 MPH.  GOLF BALL 
SIZED HAIL WAS REPORTED NEAR NEW HANDOVER SHORTLY AFTER 7 AM.   

LOCATIONS IMPACTED INCLUDE...
  FREEBURG...SCOTT AFB...MASCOUTAH...NEW ATHENS...MARISSA...LENZBURG
  AND FAYETTEVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3822 8972 3823 9009 3846 9017 3858 8971
TIME...MOT...LOC 1213Z 251DEG 36KT 3840 8995
WIND...HAIL <50MPH 1.75IN

$$

TRUETT
194 
WWUS53 KLSX 191224
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
724 AM CDT TUE APR 19 2011

ILC133-191234-
/O.CAN.KLSX.SV.W.0081.000000T0000Z-110419T1245Z/
MONROE IL-
724 AM CDT TUE APR 19 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MONROE COUNTY IS
CANCELLED...

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

LAT...LON 3834 8972 3828 8993 3829 8991 3831 8992
      3831 9003 3833 9003 3841 9014 3842 9014
      3844 9016 3846 9017 3858 8971
TIME...MOT...LOC 1224Z 251DEG 36KT 3843 8982

$$

ILC163-191245-
/O.CON.KLSX.SV.W.0081.000000T0000Z-110419T1245Z/
ST. CLAIR IL-
724 AM CDT TUE APR 19 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR ST. CLAIR 
COUNTY UNTIL 745 AM CDT...

AT 721 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED NEAR FREEBURG...MOVING EAST AT 40 MPH.

LOCATIONS IMPACTED INCLUDE...
  SCOTT AFB AND MASCOUTAH.

LAT...LON 3834 8972 3828 8993 3829 8991 3831 8992
      3831 9003 3833 9003 3841 9014 3842 9014
      3844 9016 3846 9017 3858 8971
TIME...MOT...LOC 1224Z 251DEG 36KT 3843 8982
WIND...HAIL <50MPH 1.00IN

$$

TRUETT
937 
WWUS53 KLSX 191244
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
744 AM CDT TUE APR 19 2011

ILC163-191254-
/O.EXP.KLSX.SV.W.0081.000000T0000Z-110419T1245Z/
ST. CLAIR IL-
744 AM CDT TUE APR 19 2011

...THE SEVERE THUNDERSTORM WARNING FOR ST. CLAIR COUNTY WILL EXPIRE 
AT 745 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11 AM.

LAT...LON 3834 8972 3828 8993 3829 8991 3831 8992
      3831 9003 3833 9003 3841 9014 3842 9014
      3844 9016 3846 9017 3858 8971
TIME...MOT...LOC 1244Z 251DEG 36KT 3849 8958

$$

TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 4:35 AM CDTSevere Thunderstorm WarningLSXCalhoun, Greene, Pike40 min
Apr 19, 5:14 AM CDTSevere Thunderstorm WarningLSXGreene, Pike31 min
Apr 19, 6:21 AM CDTAreal Flood AdvisoryLSXMadison, Monroe, Saint Clair3 hr
Apr 19, 6:22 AM CDTSevere Thunderstorm WarningLSXMonroe, Randolph, Saint Clair38 min
Apr 19, 6:26 AM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair49 min
Apr 19, 7:08 AM CDTSevere Thunderstorm WarningLSXJersey, Macoupin, Madison, Montgomery37 min
Apr 19, 7:36 AM CDTSevere Thunderstorm WarningLSXBond, Macoupin, Madison, Montgomery39 min
Apr 19, 8:07 AM CDTSevere Thunderstorm WarningLSXBond, Fayette, Montgomery38 min
Apr 19, 8:25 AM CDTSevere Thunderstorm WarningLSXFayette, Marion29 min
Apr 19, 8:41 AM CDTSevere Thunderstorm WarningLSXFayette34 min
Apr 19, 11:18 AM CDTRiver Flood WarningLSXCalhoun, Greene, Jersey85 days
Apr 19, 3:46 PM CDTSevere Thunderstorm WarningLSXPike44 min
Apr 19, 3:59 PM CDTTornado WarningLSXPike46 min
Apr 19, 4:18 PM CDTTornado WarningLSXCalhoun, Greene, Pike42 min
Apr 19, 4:31 PM CDTTornado WarningLSXCalhoun44 min
Apr 19, 4:41 PM CDTSevere Thunderstorm WarningLSXCalhoun, Greene, Jersey, Macoupin, Madison49 min
Apr 19, 4:59 PM CDTTornado WarningLSXGreene, Pike46 min
Apr 19, 5:28 PM CDTSevere Thunderstorm WarningLSXGreene, Jersey, Macoupin47 min
Apr 19, 5:28 PM CDTSevere Thunderstorm WarningLSXCalhoun47 min
Apr 19, 5:36 PM CDTTornado WarningLSXMacoupin39 min
Apr 19, 5:42 PM CDTSevere Thunderstorm WarningLSXGreene34 min
Apr 19, 5:44 PM CDTSevere Thunderstorm WarningLSXCalhoun, Jersey34 min
Apr 19, 6:01 PM CDTTornado WarningLSXMontgomery44 min
Apr 19, 6:05 PM CDTTornado WarningLSXMacoupin, Montgomery40 min
Apr 19, 6:12 PM CDTSevere Thunderstorm WarningLSXCalhoun48 min
Apr 19, 6:14 PM CDTSevere Thunderstorm WarningLSXJersey, Macoupin, Madison61 min
Apr 19, 6:31 PM CDTTornado WarningLSXMontgomery27 min
Apr 19, 6:56 PM CDTSevere Thunderstorm WarningLSXBond, Macoupin, Madison, Montgomery64 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2011Every severe thunderstorm warning 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.