Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 218, NWS St. Louis, MO

July 8, 2012Saint Louis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 8, 2012, 7:29 PM CDT for Saint Louis County, Missouri. It was in force for 46 min. 5 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
Jul 8, 2012, 7:29 PM CDT (00:29 UTC)
Expired
Jul 8, 2012, 8:15 PM CDT
In force
46 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Saint Louis County, MO

The radar

The St Louis radar (KLSX), 36 km from the middle of the area, began a volume at 00:31 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
Jul 8, 7:35 PM CDTTSTM WND GST 60Mehlville, MOTREE BRANCHES OF 6 TO 8 INCH DIAMETER WERE DOWN. HAIL OF 0.50 INCH FELL AT THIS LOCATION.
Jul 8, 7:35 PM CDTHAIL 0.25Sunset Hills, MOPEA SIZE HAIL OVER SUNSET HILLS
Jul 8, 7:41 PM CDTTSTM WND GST 62Shrewsbury, MOWIND SET MEASURED GUSTS TO 62 MPH.
Jul 8, 7:43 PM CDTHAIL 1Mehlville, MO
Jul 8, 8:00 PM CDTTSTM WND DMGAffton, MOTREE DOWN AND HOUSE DAMAGE IN AFFTON AROUND 8 PM. REPORT RELAYED BY LOCAL BROADCAST MEDIA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.5 hours before the alert went out and 238 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 2012-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 62 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 2012-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -53 square meters per square second.1939Sfc1 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
62 J/kg
Mixed-layer CIN
-271 J/kg
Mixed-layer LCL
1549 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-53 m²/s²
0-3 km storm-relative helicity
32 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.

452 
WUUS53 KLSX 090029
SVRLSX
MOC189-090115-
/O.NEW.KLSX.SV.W.0218.120709T0029Z-120709T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
729 PM CDT SUN JUL 8 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 815 PM CDT

* AT 723 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR MEHLVILLE...
  AND MOVING WEST AT 10 MPH.

  HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED. THIS STORM HAS HAD A HISTORY OF LARGE 
           HAIL TO GOLF BALLS AND DAMAGING WINDS...BUT NOTHING 
           HAS BEEN RECEIVED RECENTLY. 

  IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS. MINOR TREE
           DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER BROKEN.

* LOCATIONS IMPACTED INCLUDE...
  AFFTON...SHREWSBURY...LAKESHIRE...WEBSTER GROVES...CRESTWOOD...
  GLENDALE...OAKLAND...WARSON WOODS...SUNSET HILLS...KIRKWOOD AND
  FRONTENAC.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 3846 9029 3842 9034 3842 9035 3846 9034
      3846 9040 3847 9042 3850 9040 3850 9044
      3864 9042 3859 9031 3858 9032 3853 9026
TIME...MOT...LOC 0028Z 096DEG 7KT 3852 9033

HAIL...1.00IN
WIND...60 MPH

$$

TES
2 follow-up statements
890 
WWUS53 KLSX 090046
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
746 PM CDT SUN JUL 8 2012

MOC189-090115-
/O.CON.KLSX.SV.W.0218.000000T0000Z-120709T0115Z/
ST. LOUIS MO-
746 PM CDT SUN JUL 8 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTH CENTRAL
ST. LOUIS COUNTY UNTIL 815 PM CDT...

AT 740 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED FROM AFFTON TO 
MEHLVILLE...AND MOVING WEST AT 10 MPH.

HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

SOURCE...TRAINED WEATHER SPOTTERS REPORTED UP TO 8 INCH DIAMETER 
         TREE LIMBS DOWNED AT MEHLVILLE AT 735 PM. ALSO...QUARTER 
         SIZED HAIL WAS ALSO REPORTED AT MEHLVILLE AT 744 PM.

IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS. MINOR TREE
         DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER BROKEN.

LOCATIONS IMPACTED INCLUDE...
WEBSTER GROVES...GLENDALE...CRESTWOOD...OAKLAND...WARSON WOODS...
FRONTENAC...SUNSET HILLS AND KIRKWOOD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

TO REPORT SEVERE WEATHER CONTACT YOUR NEAREST LAW ENFORCEMENT AGENCY.
THEY WILL SEND YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN ST
LOUIS.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 3846 9029 3842 9034 3842 9035 3846 9034
      3846 9040 3847 9042 3850 9040 3850 9044
      3864 9042 3859 9031 3858 9032 3853 9026
TIME...MOT...LOC 0044Z 087DEG 8KT 3855 9034

HAIL...1.00IN
WIND...60 MPH

$$

TES
503 
WWUS53 KLSX 090108
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
808 PM CDT SUN JUL 8 2012

MOC189-090119-
/O.EXP.KLSX.SV.W.0218.000000T0000Z-120709T0115Z/
ST. LOUIS MO-
808 PM CDT SUN JUL 8 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL ST. LOUIS COUNTY
WILL EXPIRE AT 815 PM CDT...

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 AND HEAVY RAIN ARE STILL POSSIBLE WITH THIS
THUNDERSTORM.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN ST LOUIS.

LAT...LON 3846 9029 3842 9034 3842 9035 3846 9034
      3846 9040 3847 9042 3850 9040 3850 9044
      3864 9042 3859 9031 3858 9032 3853 9026
TIME...MOT...LOC 0109Z 087DEG 8KT 3855 9041

$$

TES

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 8:35 PM CDTAreal Flood AdvisoryLSXSaint Louis, City of Saint Louis6 hr
Jul 8, 9:55 PM CDTFlash Flood WarningLSXGasconade5 hr
Jul 9, 12:05 AM CDTAreal Flood AdvisoryLSXCole, Moniteau, Osage6 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.