Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 217, NWS St. Louis, MO

July 8, 2012Saint Louis County, City of Saint Louis, Missouri; Saint Clair County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 8, 2012, 6:49 PM CDT for Saint Louis County, City of Saint Louis, Missouri; Saint Clair County, Illinois. It was in force for 41 min. 6 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, 6:49 PM CDT (23:49 UTC)
Expired
Jul 8, 2012, 7:30 PM CDT
In force
41 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Saint Clair County, IL, City of Saint Louis, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 45 km from the middle of the area, began a volume at 23:49 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, 6:59 PM CDTHAIL 1.75Dupo, IL
Jul 8, 7:00 PM CDTHAIL 1.75East Carondelet, ILGOLF BALL SIZE HAIL REPORTED BY AMATTEUR RADIO OPERATOR IN EAST CARONDELET
Jul 8, 7:15 PM CDTTSTM WND DMGMehlville, MOTWO TO FOUR INCH DIAMETER TREE LIMBS DOWN.
Jul 8, 7:25 PM CDTTSTM WND GST 55Mehlville, MOESTIIMATED 50 TO 55 MPH - SMALL LIMBS 1 TO 3 INCH DIAMETER..
Jul 8, 7:27 PM CDTHAIL 0.5Mehlville, MO
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.

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 12:00Z, 11.8 hours before the alert went out and 228 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 2012-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 588 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 12:00Z on 2012-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 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
588 J/kg
Mixed-layer CIN
-359 J/kg
Mixed-layer LCL
1252 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

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

862 
WUUS53 KLSX 082349
SVRLSX
ILC163-MOC189-510-090030-
/O.NEW.KLSX.SV.W.0217.120708T2349Z-120709T0030Z/

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

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...
  CENTRAL ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...
  ST. LOUIS CITY IN EAST CENTRAL MISSOURI...

* UNTIL 730 PM CDT

* AT 644 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR CAHOKIA...
  AND MOVING WEST AT 15 MPH.

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

  SOURCE...RADAR INDICATED.

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

* LOCATIONS IMPACTED INCLUDE...
  LEMAY...MEHLVILLE AND EAST CARONDELET.

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 MAY OCCUR WITH THIS STORM...AND COULD LEAD TO 
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 3849 9010 3848 9022 3852 9026 3849 9027
      3848 9028 3848 9033 3866 9030 3866 9010
TIME...MOT...LOC 2349Z 077DEG 14KT 3856 9022

HAIL...0.75IN
WIND...60 MPH

$$

TES
2 follow-up statements
139 
WWUS53 KLSX 090004
SVSLSX

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

ILC163-MOC189-510-090030-
/O.CON.KLSX.SV.W.0217.000000T0000Z-120709T0030Z/
ST. CLAIR IL-ST. LOUIS MO-ST. LOUIS CITY MO-
704 PM CDT SUN JUL 8 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR ST. LOUIS
CITY...SOUTHEASTERN ST. LOUIS AND NORTHWESTERN ST. CLAIR COUNTIES
UNTIL 730 PM CDT...

AT 701 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR EAST
CARONDELET...AND MOVING WEST AT 10 MPH.

HAZARD...GOLF BALL SIZE HAIL AND 60 MPH WIND GUSTS.

SOURCE...EMERGENCY MANAGEMENT IN SAINT CLAIR COUNTY REPORTED GOLF 
         BALL SIZED HAIL IN DUPO AT 659 PM.

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

LOCATIONS IMPACTED INCLUDE...
LEMAY AND MEHLVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DAMAGING WINDS. PEOPLE OUTSIDE
SHOULD MOVE TO A SHELTER...INSIDE A STRONG BUILDING AND AWAY FROM
WINDOWS.

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 3849 9010 3848 9022 3852 9026 3849 9027
      3848 9028 3848 9033 3866 9030 3866 9010
TIME...MOT...LOC 0004Z 082DEG 9KT 3854 9024

HAIL...1.75IN
WIND...60 MPH

$$

TES
913 
WWUS53 KLSX 090031
SVSLSX

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

ILC163-MOC189-510-090041-
/O.EXP.KLSX.SV.W.0217.000000T0000Z-120709T0030Z/
ST. CLAIR IL-ST. LOUIS MO-ST. LOUIS CITY MO-
731 PM CDT SUN JUL 8 2012

...THE SEVERE THUNDERSTORM WARNING FOR ST. LOUIS CITY AND 
NORTHWESTERN ST. CLAIR COUNTIES HAS EXPIRED...
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEAST ST. LOUIS COUNTY 
HAS BEEN REISSUED...

PLEASE REFER TO THAT BULLETIN FOR THE LATEST SEVERE WEATHER
INFORMATION.  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 3849 9010 3848 9022 3852 9026 3849 9027
      3848 9028 3848 9033 3866 9030 3866 9010
TIME...MOT...LOC 0004Z 082DEG 9KT 3854 9024

$$

TES

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, 7:18 PM CDTSevere Thunderstorm WarningLSXJefferson, Saint Louis27 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 7, 8:40 PM CDTSevere Thunderstorm WarningLSXSaint Clair50 min
Jul 8, 2:29 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Fayette, Marion46 min
Jul 8, 5:03 PM CDTSevere Thunderstorm WarningLSXRandolph42 min
Jul 8, 5:42 PM CDTSevere Thunderstorm WarningLSXRandolph48 min
Jul 8, 5:44 PM CDTSevere Thunderstorm WarningLSXMonroe46 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2012Severe Thunderstorm Warnings in Illinois, 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.