Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 491, NWS St. Louis, MO

August 12, 20114 counties in Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Aug 12, 2011, 5:22 PM CDT for 4 counties in Missouri. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 12, 2011, 5:22 PM CDT (22:22 UTC)
Expired
Aug 12, 2011, 6:00 PM CDT
In force
38 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Iron County, MO, Madison County, MO, Reynolds County, MO, Saint Francois County, MO

The radar

The St Louis radar (KLSX), 162 km from the middle of the area, began a volume at 22:23 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.

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 10.4 hours before the alert went out and 265 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, Springfield, MO at 12:00Z on 2011-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 196 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, Springfield, MO at 12:00Z on 2011-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 146 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
196 J/kg
Mixed-layer CIN
-283 J/kg
Mixed-layer LCL
1165 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
146 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

645 
WUUS53 KLSX 122222
SVRLSX
MOC093-123-179-187-122300-
/O.NEW.KLSX.SV.W.0491.110812T2222Z-110812T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
522 PM CDT FRI AUG 12 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  IRON COUNTY IN SOUTHEAST MISSOURI...
  MADISON COUNTY IN SOUTHEAST MISSOURI...
  REYNOLDS COUNTY IN SOUTHEAST MISSOURI...
  SOUTHERN ST. FRANCOIS COUNTY IN SOUTHEAST MISSOURI...

* UNTIL 600 PM CDT

* AT 519 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM 7 MILES WEST OF BELLEVIEW TO 5
  MILES EAST OF REYNOLDS TO 7 MILES NORTHWEST OF EMINENCE...AND
  MOVING EAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  IRONTON...FREDERICKTOWN...BELLEVIEW...IRON MOUNTAIN...PILOT KNOB...
  GLOVER...ARCADIA...ELLINGTON...ANNAPOLIS...ROSELLE...SACO...
  GARWOOD...JUNCTION CITY...BUCKHORN...MARQUAND...LESTERVILLE...
  REDFORD...GRANITE...HOGAN AND CHLORIDE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3705 9096 3709 9097 3709 9101 3716 9104
      3720 9109 3720 9113 3725 9113 3726 9117
      3738 9118 3740 9109 3773 9085 3763 9016
      3731 9016 3731 9054 3727 9055 3727 9073
      3717 9073 3713 9077 3705 9077
TIME...MOT...LOC 2222Z 288DEG 25KT 3768 9085 3737 9096
          3724 9138
WIND...HAIL 60MPH 1.00IN

$$

GKS
2 follow-up statements
074 
WWUS53 KLSX 122251
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
551 PM CDT FRI AUG 12 2011

MOC187-122300-
/O.CAN.KLSX.SV.W.0491.000000T0000Z-110812T2300Z/
ST. FRANCOIS MO-
551 PM CDT FRI AUG 12 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN ST. FRANCOIS COUNTY
IS CANCELLED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE MOVED OUT OF THE 
WARNED AREA.

LAT...LON 3705 9096 3709 9097 3709 9101 3716 9104
      3720 9109 3720 9113 3725 9113 3726 9117
      3735 9112 3740 9107 3765 9079 3763 9016
      3731 9016 3731 9054 3727 9055 3727 9073
      3717 9073 3713 9077 3705 9077
TIME...MOT...LOC 2250Z 288DEG 25KT 3762 9046 3729 9068
          3713 9098

$$

MOC093-123-179-122300-
/O.CON.KLSX.SV.W.0491.000000T0000Z-110812T2300Z/
IRON MO-MADISON MO-REYNOLDS MO-
551 PM CDT FRI AUG 12 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR REYNOLDS...
MADISON AND IRON COUNTIES UNTIL 600 PM CDT...

AT 545 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM ROSELLE TO ANNAPOLIS TO 7 MILES
SOUTHWEST OF ELLINGTON...MOVING EAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  FREDERICKTOWN...GARWOOD...SACO...JUNCTION CITY...BUCKHORN...
  MARQUAND...DES ARC...CATHERINE PLACE AND MINE LA MOTTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3705 9096 3709 9097 3709 9101 3716 9104
      3720 9109 3720 9113 3725 9113 3726 9117
      3735 9112 3740 9107 3765 9079 3763 9016
      3731 9016 3731 9054 3727 9055 3727 9073
      3717 9073 3713 9077 3705 9077
TIME...MOT...LOC 2250Z 288DEG 25KT 3762 9046 3729 9068
          3713 9098
WIND...HAIL 60MPH 1.00IN

$$

GKS
280 
WWUS53 KLSX 122304
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
604 PM CDT FRI AUG 12 2011

MOC093-123-179-122313-
/O.EXP.KLSX.SV.W.0491.000000T0000Z-110812T2300Z/
IRON MO-MADISON MO-REYNOLDS MO-
604 PM CDT FRI AUG 12 2011

...THE SEVERE THUNDERSTORM WARNING FOR REYNOLDS...MADISON AND IRON
COUNTIES HAS EXPIRED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED BELOW
SEVERE LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR
PROPERTY.  HOWEVER SMALL HAIL...GUSTY WINDS AND HEAVY RAIN ARE STILL 
POSSIBLE WITH THESE THUNDERSTORMS FOR ANOTHER 30 MINUTES.

LAT...LON 3705 9096 3709 9097 3709 9101 3716 9104
      3720 9109 3720 9113 3725 9113 3726 9117
      3735 9112 3740 9107 3765 9079 3763 9016
      3731 9016 3731 9054 3727 9055 3727 9073
      3717 9073 3713 9077 3705 9077
TIME...MOT...LOC 2251Z 288DEG 25KT 3762 9045 3729 9067
          3713 9097

$$

GKS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 4:44 PM CDTSevere Thunderstorm WarningLSXCrawford, Iron, Jefferson, Madison, Reynolds, Sainte Genevieve and 2 more46 min
Aug 12, 5:25 PM CDTSevere Thunderstorm WarningLSXMadison, Sainte Genevieve, Saint Francois50 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.