Alert archive / Illinois / Tornado Warnings in 2012

Tornado Warning 15, NWS St. Louis, MO

April 28, 2012Saint Clair County, Illinois

NWS St. Louis, MO issued this tornado warning at Apr 28, 2012, 3:59 PM CDT for Saint Clair County, Illinois. It was in force for 31 min. 30 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 28, 2012, 3:59 PM CDT (20:59 UTC)
Expired
Apr 28, 2012, 4:30 PM CDT
In force
31 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
2.5 in

County Saint Clair County, IL

The radar

The St Louis radar (KLSX), 67 km from the middle of the area, began a volume at 21:01 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 28, 3:59 PM CDTHAIL 1.75Fairmont City, ILAT CAHOKIA MOUNDS
Apr 28, 4:03 PM CDTHAIL 1.75Fairview Heights, IL
Apr 28, 4:03 PM CDTHAIL 2Fairview Heights, ILLEAVES SHREDDED FROM TREES. DAMAGED ROOF SHINGLES. DENTS ON CARS.
Apr 28, 4:05 PM CDTFUNNEL CLOUDO'Fallon, ILON NORTH SIDE OF OFALLON LOOKING WEST
Apr 28, 4:05 PM CDTHAIL 2.2Fairview Heights, IL
Apr 28, 4:05 PM CDTHAIL 2.5Fairview Heights, ILNEAR US HWY AND BUNKUM RD
Apr 28, 4:10 PM CDTFUNNEL CLOUDBelleville, ILOBSERVED NEAR BELLEVILLE EAST HIGH SCHOOL REACH HALF WAY TO THE GROUND
Apr 28, 4:10 PM CDTHAIL 1.75O'Fallon, IL
Apr 28, 4:10 PM CDTHAIL 2O'Fallon, ILEST 60 TO 70 MPH WINDS...NEAR GREEN MOUNT RD AND I 64
Apr 28, 4:12 PM CDTHAIL 2.5O'Fallon, IL
Apr 28, 4:14 PM CDTHAIL 2Fairview Heights, IL
Apr 28, 4:15 PM CDTHAIL 1.75Lebanon, ILWIND EST 50 MPH...SMALL TREE BRANCHES DOWN
Apr 28, 4:15 PM CDTHAIL 2.75O'Fallon, ILCOVERING THE GROUND 3 INCHES DEEP
Apr 28, 4:15 PM CDTHAIL 3.5O'Fallon, ILRELAYED FROM A NWS EMPLOYEE. RELATIVE OF EMPLOYEE REPORTED 3.5 BY 2 INCH HAIL. DISC SHAPED. LASTED FOR ABOUT 10 MINUTES.
Apr 28, 4:19 PM CDTHAIL 1.75Scott Afb, IL
Apr 28, 4:19 PM CDTHAIL 2.5O'Fallon, IL
Apr 28, 4:20 PM CDTTSTM WND DMGShiloh, IL8 TO 10 INCH LIMBS DOWN
Apr 28, 4:20 PM CDTHAIL 2.52 S Lebanon, IL
Apr 28, 4:22 PM CDTHAIL 2.75Lebanon, ILHAIL DAMAGED NUMEROUS CAR WINDSHIELDS AND HOME WINDOWS AS WELL.
Apr 28, 4:23 PM CDTHAIL 0.5Belleville, IL
Apr 28, 4:25 PM CDTHAIL 1.75Belleville, IL
Apr 28, 4:26 PM CDTHAIL 1.75Belleville, IL
Apr 28, 4:27 PM CDTHAIL 2.75Belleville, ILAT SCOTT AFB
Apr 28, 4:28 PM CDTHAIL 1Belleville, ILEAST PART OF BELLEVILLE
Apr 28, 4:29 PM CDTHAIL 1Swansea, IL
Apr 28, 4:30 PM CDTTSTM WND DMGO'Fallon, ILSEVERAL LARGE METAL ROAD SIGNS BLOWN DOWN BETWEEN OFALLON AND THE COUNTY LINE ALONG I 64...ALSO A FEW LARGE TREES WERE SNAPPED ACROSS THE SOUTHEAST PORTION OF OFALLON JUST NORTH OF I 64
Apr 28, 4:30 PM CDTHAIL 1.751 W Shiloh, ILCOVERING THE GROUND
Apr 28, 4:30 PM CDTHAIL 22 Wnw Belleville, ILJUST ENDED
Apr 28, 4:30 PM CDTHAIL 3Belleville, ILDAMAGE TO MOTOR VEHICLES.
Apr 28, 4:38 PM CDTHAIL 0.7Shiloh, 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 28, 1:48 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.0 hours before the alert went out and 207 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 12:00Z on 2012-04-28Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2012-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 681 square meters per square second.19395878Sfc1 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
1019 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
681 m²/s²
0-3 km storm-relative helicity
811 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.0

Open this sounding in Storm Lab

The text

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

076 
WFUS53 KLSX 282059
TORLSX
ILC163-282130-
/O.NEW.KLSX.TO.W.0015.120428T2059Z-120428T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
359 PM CDT SAT APR 28 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 430 PM CDT

* AT 357 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR CASEYVILLE...AND MOVING EAST AT 30 MPH.

  HAZARD...DEVELOPING TORNADO AND TENNIS BALL SIZE HAIL.

  SOURCE...RADAR INDICATED ROTATION.

  IMPACT...SIGNIFICANT HOUSE AND BUILDING DAMAGE POSSIBLE. MOBILE
           HOMES COMPLETELY DESTROYED IF HIT. SOME TREES UPROOTED OR
           SNAPPED. VEHICLES WILL LIKELY BE THROWN BY TORNADIC WINDS.

* LOCATIONS IMPACTED INCLUDE...
  FAIRVIEW HEIGHTS...BELLEVILLE...SWANSEA...O'FALLON...SHILOH...SCOTT
  AFB AND LEBANON.

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.

&&

LAT...LON 3865 8973 3845 8989 3855 9016 3866 9010
TIME...MOT...LOC 2059Z 290DEG 27KT 3861 9004

TORNADO...RADAR INDICATED
HAIL...2.50IN

$$

BYRD
1 follow-up statement
555 
WWUS53 KLSX 282130
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
430 PM CDT SAT APR 28 2012

ILC163-282140-
/O.EXP.KLSX.TO.W.0015.000000T0000Z-120428T2130Z/
ST. CLAIR IL-
430 PM CDT SAT APR 28 2012

...THE TORNADO WARNING FOR NORTHERN ST. CLAIR COUNTY HAS EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA AND WAS NO LONGER SHOWING STRONG ROTATION WITH IT...BUT IT 
REMAINS SEVERE...PRODUCING LARGE HAIL AND DAMAGING WINDS AS IT MOVES 
TO THE EAST.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 7 PM.

LAT...LON 3865 8973 3845 8989 3855 9016 3866 9010
TIME...MOT...LOC 2130Z 290DEG 27KT 3853 8976

$$

BYRD

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 28, 2:26 PM CDTSevere Thunderstorm WarningLSXCalhoun49 min
Apr 28, 3:05 PM CDTSevere Thunderstorm WarningLSXCalhoun, Jersey, Madison40 min
Apr 28, 3:45 PM CDTSevere Thunderstorm WarningLSXClinton, Madison, Saint Clair45 min
Apr 28, 4:22 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington38 min
Apr 28, 4:28 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington47 min
Apr 28, 4:56 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington49 min
Apr 28, 5:13 PM CDTSevere Thunderstorm WarningLSXClinton, Marion, Washington47 min
Apr 28, 5:38 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington37 min
Apr 28, 5:50 PM CDTSevere Thunderstorm WarningLSXCalhoun40 min
Apr 28, 6:01 PM CDTTornado WarningLSXMadison, Saint Clair29 min
Apr 28, 6:10 PM CDTSevere Thunderstorm WarningLSXMonroe34 min
Apr 28, 6:17 PM CDTSevere Thunderstorm WarningLSXClinton, Washington33 min
Apr 28, 6:27 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair48 min
Apr 28, 6:35 PM CDTSevere Thunderstorm WarningLSXFayette, Marion25 min
Apr 28, 6:53 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington52 min
Apr 28, 6:58 PM CDTSevere Thunderstorm WarningLSXFayette, Marion32 min

Nearby

Tornado Warnings in Illinois, 2012Every tornado warning in 2012Tornadoes in 2012

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.