Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 56, NWS St. Louis, MO

April 15, 2011Jefferson County, Saint Louis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 15, 2011, 3:32 PM CDT for Jefferson County, Saint Louis County, Missouri. It was in force for 43 min. 12 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 15, 2011, 3:32 PM CDT (20:32 UTC)
Expired
Apr 15, 2011, 4:15 PM CDT
In force
43 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 25 km from the middle of the area, began a volume at 20:31 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 15, 3:42 PM CDTHAIL 0.25Cedar Hill, MO
Apr 15, 3:52 PM CDTHAIL 0.75House Springs, MO
Apr 15, 3:54 PM CDTHAIL 0.25Fenton, MO
Apr 15, 3:56 PM CDTHAIL 1High Ridge, MO
Apr 15, 3:58 PM CDTHAIL 0.25Ballwin, MO
Apr 15, 3:58 PM CDTHAIL 0.25Sunset Hills, MO
Apr 15, 3:58 PM CDTHAIL 0.88Manchester, MO
Apr 15, 4:01 PM CDTHAIL 0.25Fenton, MO
Apr 15, 4:04 PM CDTHAIL 0.25Chesterfield, MOLADUE AND OLIVE BLVD.
Apr 15, 4:05 PM CDTHAIL 0.5Chesterfield, MO
Apr 15, 4:06 PM CDTHAIL 0.25Valley Park, MO
Apr 15, 4:19 PM CDTHAIL 0.25Sunset Hills, MO3 TO 4 MINUTES OF PEA SIZE HAIL IN SUNSET HILLS

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 15, 12:47 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 8.5 hours before the alert went out and 253 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 2011-04-15Temperature 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 2011-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 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
1776 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
129 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.

396 
WUUS53 KLSX 152032
SVRLSX
MOC099-189-152115-
/O.NEW.KLSX.SV.W.0056.110415T2032Z-110415T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
332 PM CDT FRI APR 15 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  CENTRAL ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 415 PM CDT

* AT 331 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
  DITTMER...OR NEAR CEDAR HILL...AND MOVING NORTHEAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CEDAR HILL...BYRNES MILL...EUREKA...HIGH RIDGE...MURPHY...
  ELLISVILLE...FENTON...VALLEY PARK...BALLWIN...SUNSET HILLS...
  CLARKSON VALLEY...MANCHESTER...HOUSE SPRINGS...SCOTSDALE...OTTO...
  PARKDALE AND PEERLESS PARK.

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 3869 9062 3851 9037 3823 9063 3830 9076
TIME...MOT...LOC 2033Z 211DEG 28KT 3836 9067
WIND...HAIL 60MPH 1.00IN

$$

GLASS
2 follow-up statements
707 
WWUS53 KLSX 152054
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
354 PM CDT FRI APR 15 2011

MOC099-189-152115-
/O.CON.KLSX.SV.W.0056.000000T0000Z-110415T2115Z/
JEFFERSON MO-ST. LOUIS MO-
354 PM CDT FRI APR 15 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL ST.
LOUIS AND NORTH CENTRAL JEFFERSON COUNTIES UNTIL 415 PM CDT...

AT 351 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
HOUSE SPRINGS...OR NEAR BYRNES MILL...MOVING NORTHEAST AT 30 MPH.

IN ADDITION...AT 352 PM PENNY SIZE HAIL WAS REPORTED IN HOUSE 
SPRINGS WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  EUREKA...HIGH RIDGE...MURPHY...ELLISVILLE...FENTON...VALLEY PARK...
  BALLWIN...CLARKSON VALLEY...SUNSET HILLS...MANCHESTER...
  CHESTERFIELD...PARKDALE AND PEERLESS PARK.

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 3833 9054 3846 9069 3869 9062 3851 9037
TIME...MOT...LOC 2054Z 215DEG 26KT 3843 9054
WIND...HAIL 60MPH 1.00IN

$$

GLASS
290 
WWUS53 KLSX 152117
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
417 PM CDT FRI APR 15 2011

MOC099-189-152127-
/O.EXP.KLSX.SV.W.0056.000000T0000Z-110415T2115Z/
JEFFERSON MO-ST. LOUIS MO-
417 PM CDT FRI APR 15 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL ST. LOUIS AND 
NORTH CENTRAL JEFFERSON COUNTIES HAS EXPIRED...

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 3833 9054 3846 9069 3869 9062 3851 9037
TIME...MOT...LOC 2054Z 215DEG 26KT 3843 9054

$$

GLASS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 15, 1:09 PM CDTSevere Thunderstorm WarningLSXLincoln, Pike51 min
Apr 15, 1:53 PM CDTSevere Thunderstorm WarningLSXPike35 min
Apr 15, 2:00 PM CDTSevere Thunderstorm WarningLSXLewis, Marion, Ralls45 min
Apr 15, 2:20 PM CDTSevere Thunderstorm WarningLSXFranklin, Saint Charles, Warren40 min
Apr 15, 2:23 PM CDTSevere Thunderstorm WarningLSXMarion, Ralls22 min
Apr 15, 2:52 PM CDTSevere Thunderstorm WarningLSXMarion, Ralls53 min
Apr 15, 2:54 PM CDTSevere Thunderstorm WarningLSXFranklin, Jefferson, Lincoln, Pike, Saint Charles, Saint Louis and 1 more51 min
Apr 15, 3:52 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Francois38 min
Apr 15, 4:03 PM CDTSevere Thunderstorm WarningLSXSaint Charles, Saint Louis, City of Saint Louis42 min
Apr 15, 4:21 PM CDTSevere Thunderstorm WarningLSXJefferson39 min
Apr 15, 4:43 PM CDTSevere Thunderstorm WarningLSXSaint Charles, Saint Louis, City of Saint Louis47 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.