Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 128, NWS St. Louis, MO

April 28, 2012Jefferson County, Missouri; Monroe County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 28, 2012, 8:39 PM CDT for Jefferson County, Missouri; Monroe County, Illinois. It was in force for 36 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 28, 2012, 8:39 PM CDT (01:39 UTC)
Expired
Apr 28, 2012, 9:15 PM CDT
In force
36 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Monroe County, IL, Jefferson County, MO

The radar

The St Louis radar (KLSX), 55 km from the middle of the area, began a volume at 01:40 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, 8:53 PM CDTHAIL 1.25Valmeyer, IL
Apr 28, 9:00 PM CDTTSTM WND GST 70Foster Pond, ILTWO SMALL BUILDINGS HAD THEIR ROOFS BLOWN OFF. A COUPLE TREES BLOW OVER.
Apr 28, 9:01 PM CDTHAIL 1.52 E Wartburg, ILAT INTERSECTION OF ILLINOIS ROUTE 3 AND KASKASKIA ROAD.
Apr 28, 9:03 PM CDTHAIL 0.5Waterloo, 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
Apr 28, 5:15 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.7 hours before the alert went out and 247 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 2012-04-29Temperature 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 00:00Z on 2012-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 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
545 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
141 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.

561 
WUUS53 KLSX 290139
SVRLSX
ILC133-MOC099-290230-
/O.NEW.KLSX.SV.W.0128.120429T0139Z-120429T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
839 PM CDT SAT APR 28 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL MONROE COUNTY IN SOUTHWEST ILLINOIS...
  EAST CENTRAL JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 930 PM CDT

* AT 836 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR BARNHART...
  AND MOVING EAST AT 25 MPH.

  HAZARD...QUARTER SIZE HAIL.

  SOURCE...TRAINED WEATHER SPOTTERS REPORTED QUARTER SIZE HAIL IN    
  OTTO.

  IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS.

* LOCATIONS IMPACTED INCLUDE...
  CRYSTAL CITY...WATERLOO...VALMEYER...FOUNTAIN...NEW DESIGN...
  HARRISONVILLE...MONROE CITY...CHALFIN BRIDGE...NEW HANDOVER...
  MADONNAVILLE...FOSTER POND...MAEYSTOWN...WARTBURG AND BURKSVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3818 9009 3824 9048 3844 9042 3843 9035
      3839 9034 3842 9030 3841 9015 3835 9007
TIME...MOT...LOC 0138Z 280DEG 23KT 3834 9037

HAIL...1.00IN
WIND...<50 MPH

$$

KANOFSKY
2 follow-up statements
603 
WWUS53 KLSX 290154
SVSLSX

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

MOC099-290204-
/O.CAN.KLSX.SV.W.0128.000000T0000Z-120429T0230Z/
JEFFERSON MO-
854 PM CDT SAT APR 28 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL JEFFERSON COUNTY
IS CANCELLED...

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

LAT...LON 3818 9009 3822 9036 3826 9037 3833 9037
      3839 9034 3842 9030 3841 9015 3835 9007
TIME...MOT...LOC 0154Z 280DEG 23KT 3832 9024

$$

ILC133-290230-
/O.CON.KLSX.SV.W.0128.000000T0000Z-120429T0230Z/
MONROE IL-
854 PM CDT SAT APR 28 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL MONROE
COUNTY UNTIL 930 PM CDT...

AT 850 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR FOUNTAIN...AND
MOVING EAST AT 25 MPH.

HAZARD...HALF DOLLAR SIZE HAIL.

SOURCE...TRAINED WEATHER SPOTTERS.

IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS.

IN ADDITION...HALF DOLLAR SIZE HAIL WAS REPORTED NEAR VALMEYER WITH 
THIS STORM.

LOCATIONS IMPACTED INCLUDE...
WATERLOO...NEW DESIGN...FOSTER POND...MAEYSTOWN...WARTBURG AND
BURKSVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3818 9009 3822 9036 3826 9037 3833 9037
      3839 9034 3842 9030 3841 9015 3835 9007
TIME...MOT...LOC 0154Z 280DEG 23KT 3832 9024

HAIL...1.25IN
WIND...<50 MPH

$$

KANOFSKY
328 
WWUS53 KLSX 290215
SVSLSX

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

ILC133-290224-
/O.CAN.KLSX.SV.W.0128.000000T0000Z-120429T0230Z/
MONROE IL-
915 PM CDT SAT APR 28 2012

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

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

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 10 PM CDT.

LAT...LON 3818 9009 3822 9036 3826 9037 3833 9037
      3839 9034 3842 9030 3841 9015 3835 9007
TIME...MOT...LOC 0214Z 280DEG 23KT 3830 9008

$$

KANOFSKY

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 28, 8:12 PM CDTSevere Thunderstorm WarningLSXJefferson, Saint Louis48 min
Apr 29, 1:44 AM CDTSevere Thunderstorm WarningLSXSaint Charles, Saint Louis, City of Saint Louis46 min
Apr 29, 1:47 AM CDTSevere Thunderstorm WarningLSXBoone, Callaway, Cole32 min
Apr 29, 2:22 AM CDTSevere Thunderstorm WarningLSXAudrain, Boone38 min
Apr 29, 2:52 AM CDTSevere Thunderstorm WarningLSXMonroe38 min
Apr 29, 3:05 AM CDTSevere Thunderstorm WarningLSXCallaway44 min
Apr 29, 4:00 AM CDTSevere Thunderstorm WarningLSXLincoln, Montgomery, Pike27 min
Apr 29, 4:59 AM CDTSevere Thunderstorm WarningLSXLincoln, Pike46 min
Apr 29, 4:00 PM CDTFlash Flood WatchLSXAudrain, Boone, Callaway, Cole, Crawford, Franklin and 14 more15 hr
Apr 28, 7:41 PM CDTAreal Flood AdvisoryLSXClinton, Saint Clair, Washington6 hr
Apr 28, 9:05 PM CDTSevere Thunderstorm WarningLSXMonroe, Randolph, Saint Clair33 min
Apr 28, 9:31 PM CDTSevere Thunderstorm WarningLSXRandolph, Saint Clair, Washington33 min
Apr 28, 10:01 PM CDTSevere Thunderstorm WarningLSXBond, Macoupin, Madison, Montgomery34 min
Apr 28, 10:25 PM CDTSevere Thunderstorm WarningLSXMacoupin, Montgomery28 min
Apr 29, 5:32 AM CDTSevere Thunderstorm WarningLSXGreene, Jersey36 min
Apr 29, 7:54 AM CDTFlash Flood WarningLSXMacoupin, Montgomery6 hr
Apr 29, 7:58 AM CDTSevere Thunderstorm WarningLSXMontgomery20 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2012Severe Thunderstorm Warnings in Illinois, 2012Every severe thunderstorm warning 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.