Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 203, NWS St. Louis, MO

July 7, 2012Jefferson County, Saint Louis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 7, 2012, 7:18 PM CDT for Jefferson County, Saint Louis County, Missouri. It was in force for 27 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
Jul 7, 2012, 7:18 PM CDT (00:18 UTC)
Expired
Jul 7, 2012, 7:45 PM CDT
In force
27 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 23 km from the middle of the area, began a volume at 00:21 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

Lincoln, IL (KILX), launched 00:00Z, 0.3 hours before the alert went out and 254 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 2012-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 199 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 2012-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 square meters per square second.193958Sfc1 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
199 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
2803 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
1 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.

672 
WUUS53 KLSX 080018
SVRLSX
MOC099-189-080100-
/O.NEW.KLSX.SV.W.0203.120708T0018Z-120708T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
718 PM CDT SAT JUL 7 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 800 PM CDT

* AT 717 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR HIGH
  RIDGE...AND MOVING SOUTHWEST AT 15 MPH.

  HAZARD...60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED.

  IMPACT...MINOR TREE DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER
           BROKEN.

* LOCATIONS IMPACTED INCLUDE...
  HIGH RIDGE...EUREKA...BYRNES MILL...HOUSE SPRINGS AND SCOTSDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3845 9074 3849 9073 3864 9063 3852 9061
      3854 9045 3835 9053
TIME...MOT...LOC 0018Z 026DEG 11KT 3850 9057

HAIL...<.75IN
WIND...60 MPH

$$

KANOFSKY
2 follow-up statements
433 
WWUS53 KLSX 080035
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
735 PM CDT SAT JUL 7 2012

MOC099-189-080100-
/O.CON.KLSX.SV.W.0203.000000T0000Z-120708T0100Z/
JEFFERSON MO-ST. LOUIS MO-
735 PM CDT SAT JUL 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
ST. LOUIS AND NORTHWESTERN JEFFERSON COUNTIES UNTIL 800 PM CDT...

AT 729 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR BYRNES MILL...
AND MOVING SOUTHWEST AT 15 MPH.

HAZARD...60 MPH WIND GUSTS.

SOURCE...TRAINED WEATHER SPOTTERS REPORTED TREES DOWN IN ELLISVILLE  
         WITH THIS STORM.

IMPACT...MINOR TREE DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER
         BROKEN.

LOCATIONS IMPACTED INCLUDE...
EUREKA...BYRNES MILL...HOUSE SPRINGS AND SCOTSDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3845 9074 3849 9073 3864 9063 3852 9061
      3854 9045 3835 9053
TIME...MOT...LOC 0034Z 026DEG 11KT 3846 9060

HAIL...<.75IN
WIND...60 MPH

$$

KANOFSKY
836 
WWUS53 KLSX 080045
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
745 PM CDT SAT JUL 7 2012

MOC099-189-080055-
/O.CAN.KLSX.SV.W.0203.000000T0000Z-120708T0100Z/
JEFFERSON MO-ST. LOUIS MO-
745 PM CDT SAT JUL 7 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN ST. LOUIS AND
NORTHWESTERN JEFFERSON COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
 HOWEVER GUSTY WINDS ARE STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 3845 9074 3849 9073 3864 9063 3852 9061
      3854 9045 3835 9053
TIME...MOT...LOC 0045Z 026DEG 11KT 3843 9062

$$

KANOFSKY

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 7:03 PM CDTSevere Thunderstorm WarningLSXSaint Louis42 min
Jul 7, 7:06 PM CDTSevere Thunderstorm WarningLSXJefferson32 min
Jul 7, 7:10 PM CDTSevere Thunderstorm WarningLSXIron, Saint Francois, Washington39 min
Jul 7, 7:58 PM CDTSevere Thunderstorm WarningLSXJefferson47 min
Jul 7, 8:49 PM CDTSevere Thunderstorm WarningLSXWashington26 min
Jul 8, 1:36 PM CDTSevere Thunderstorm WarningLSXOsage39 min
Jul 8, 2:10 PM CDTSevere Thunderstorm WarningLSXOsage28 min
Jul 8, 3:41 PM CDTSevere Thunderstorm WarningLSXFranklin, Jefferson, Washington49 min
Jul 8, 3:53 PM CDTSevere Thunderstorm WarningLSXFranklin37 min
Jul 8, 4:24 PM CDTSevere Thunderstorm WarningLSXFranklin19 min
Jul 8, 5:57 PM CDTSevere Thunderstorm WarningLSXSaint Louis, City of Saint Louis27 min
Jul 8, 6:49 PM CDTSevere Thunderstorm WarningLSXSaint Louis, City of Saint Louis41 min

Nearby

Severe Thunderstorm Warnings in Missouri, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.