Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 111, NWS St. Louis, MO

April 19, 2011Franklin County, Jefferson County, Saint Louis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 19, 2011, 7:18 PM CDT for Franklin County, Jefferson County, Saint Louis County, Missouri. It was in force for 42 min. 8 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, 7:18 PM CDT (00:18 UTC)
Expired
Apr 19, 2011, 8:00 PM CDT
In force
42 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Franklin County, MO, Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 33 km from the middle of the area, began a volume at 00:19 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, 7:23 PM CDTHAIL 1.753 S Robertsville, MO
Apr 19, 7:33 PM CDTHAIL 0.25Lonedell, MOAT HH AND HWY 30
Apr 19, 7:39 PM CDTHAIL 0.7High Ridge, MO
Apr 19, 7:43 PM CDTHAIL 0.75Fenton, MO
Apr 19, 7:43 PM CDTHAIL 1Sunset Hills, MO
Apr 19, 7:50 PM CDTTSTM WND DMG1 Ese Fenton, MOMOBILE HOME SIDING TORN OFF
Apr 19, 7:50 PM CDTHAIL 1Sunset Hills, MO
Apr 19, 7:50 PM CDTHAIL 1.251 Ese Fenton, MOMOBILE HOME SIDING TORN OFF

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, 1:00 PM CDTTornado WatchSPC10 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.3 hours before the alert went out and 259 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 2011-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2409 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 2011-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 370 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
2409 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
547 m²/s²
Significant tornado parameter
0.0
Supercell composite
24.4

Open this sounding in Storm Lab

The text

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

053 
WUUS53 KLSX 200018
SVRLSX
MOC071-099-189-200100-
/O.NEW.KLSX.SV.W.0111.110420T0018Z-110420T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
718 PM CDT TUE APR 19 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN FRANKLIN COUNTY IN EAST CENTRAL MISSOURI...
  NORTHERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  SOUTHWESTERN ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 800 PM CDT

* AT 715 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  LONEDELL...OR 8 MILES SOUTH OF VILLA RIDGE...AND MOVING NORTHEAST
  AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  PACIFIC...CEDAR HILL...EUREKA...BYRNES MILL...ANTONIA...HIGH
  RIDGE...PEVELY...BARNHART...MURPHY...FENTON...SUNSET HILLS...
  CRESTWOOD...DITTMER...HOUSE SPRINGS...ROBERTSVILLE...OERMANN...
  CATAWISSA...MORSE MILL...MAPAVILLE AND SCOTSDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3858 9038 3826 9038 3821 9082 3841 9101
TIME...MOT...LOC 0018Z 239DEG 26KT 3838 9081
WIND...HAIL 60MPH 1.00IN

$$

GLASS
1 follow-up statement
530 
WWUS53 KLSX 200059
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
759 PM CDT TUE APR 19 2011

MOC071-099-189-200109-
/O.EXP.KLSX.SV.W.0111.000000T0000Z-110420T0100Z/
JEFFERSON MO-FRANKLIN MO-ST. LOUIS MO-
759 PM CDT TUE APR 19 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN ST. LOUIS...
SOUTHEASTERN FRANKLIN AND NORTHERN JEFFERSON COUNTIES WILL EXPIRE AT
800 PM CDT...

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 900 PM.

LAT...LON 3858 9038 3826 9038 3821 9082 3841 9101
TIME...MOT...LOC 0059Z 239DEG 26KT 3853 9049

$$

GLASS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 7:03 PM CDTSevere Thunderstorm WarningLSXCrawford, Franklin, Washington42 min
Apr 19, 7:05 PM CDTAreal Flood AdvisoryLSXSaint Louis, City of Saint Louis5 hr
Apr 19, 7:17 PM CDTSevere Thunderstorm WarningLSXIron, Madison28 min
Apr 19, 7:25 PM CDTTornado WarningLSXIron, Madison, Saint Francois40 min
Apr 19, 7:29 PM CDTSevere Thunderstorm WarningLSXIron, Madison, Sainte Genevieve, Saint Francois46 min
Apr 19, 7:30 PM CDTTornado WarningLSXSaint Louis, City of Saint Louis45 min
Apr 19, 7:34 PM CDTTornado WarningLSXMadison, Sainte Genevieve, Saint Francois41 min
Apr 19, 7:37 PM CDTTornado WarningLSXJefferson, Saint Louis36 min
Apr 19, 7:39 PM CDTTornado WarningLSXFranklin, Jefferson, Washington33 min
Apr 19, 7:48 PM CDTTornado WarningLSXMadison27 min
Apr 19, 7:54 PM CDTTornado WarningLSXSainte Genevieve36 min
Apr 19, 9:37 PM CDTSevere Thunderstorm WarningLSXSaint Charles, Saint Louis21 min

Nearby

Severe Thunderstorm Warnings in Missouri, 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.