Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 307, NWS St. Louis, MO

September 25, 2012Saint Charles County, Warren County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Sep 25, 2012, 4:31 PM CDT for Saint Charles County, Warren County, Missouri. It was in force for 44 min. 4 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
Sep 25, 2012, 4:31 PM CDT (21:31 UTC)
Expired
Sep 25, 2012, 5:15 PM CDT
In force
44 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

Counties Saint Charles County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 5 km from the middle of the area, began a volume at 21:31 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
Sep 25, 4:51 PM CDTHAIL 0.5Lake St. Louis, MO
Sep 25, 4:55 PM CDTHAIL 0.7O'Fallon, MO
Sep 25, 4:57 PM CDTHAIL 0.7O'Fallon, MOAT I-70 AND TR HUGHES BLVD...UP TO DIME SIZE HAIL WITH ALMOST NO WIND.
Sep 25, 5:02 PM CDTHAIL 0.25St. Peters, MOAT MID RIVERS MALL DRIVE AND WILLOTT ROAD...PEA SIZE HAIL.

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, 9.5 hours before the alert went out and 243 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 2012-09-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 221 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 2012-09-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 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
221 J/kg
Mixed-layer CIN
-192 J/kg
Mixed-layer LCL
560 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
134 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.7

Open this sounding in Storm Lab

The text

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

230 
WUUS53 KLSX 252131
SVRLSX
MOC183-219-252215-
/O.NEW.KLSX.SV.W.0307.120925T2131Z-120925T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
431 PM CDT TUE SEP 25 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL ST. CHARLES COUNTY IN EAST CENTRAL MISSOURI...
  EAST CENTRAL WARREN COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 515 PM CDT

* AT 426 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR
  MARTHASVILLE...AND MOVING EAST AT 40 MPH.

  HAZARD...HALF DOLLAR SIZE HAIL AND 60 MPH WIND GUSTS.

  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...
  LAKE ST. LOUIS...DARDENNE PRAIRIE...O'FALLON...WELDON SPRING...
  COTTLEVILLE...ST. PETERS AND NEW MELLE.

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.

&&

LAT...LON 3886 9057 3868 9058 3868 9063 3869 9065
      3868 9068 3867 9068 3866 9069 3865 9113
      3872 9114
TIME...MOT...LOC 2131Z 263DEG 34KT 3868 9103

HAIL...1.25IN
WIND...60 MPH

$$

TES
2 follow-up statements
257 
WWUS53 KLSX 252148
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
448 PM CDT TUE SEP 25 2012

MOC219-252158-
/O.CAN.KLSX.SV.W.0307.000000T0000Z-120925T2215Z/
WARREN MO-
448 PM CDT TUE SEP 25 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL WARREN COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

LAT...LON 3868 9058 3868 9063 3869 9065 3868 9068
      3866 9069 3866 9093 3877 9095 3886 9057
TIME...MOT...LOC 2148Z 263DEG 34KT 3870 9083

$$

MOC183-252215-
/O.CON.KLSX.SV.W.0307.000000T0000Z-120925T2215Z/
ST. CHARLES MO-
448 PM CDT TUE SEP 25 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL ST.
CHARLES COUNTY UNTIL 515 PM CDT...

AT 445 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR NEW MELLE...
AND MOVING EAST AT 40 MPH.

HAZARD...HALF DOLLAR SIZE HAIL AND 60 MPH WIND GUSTS.

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...
LAKE ST. LOUIS...DARDENNE PRAIRIE...O'FALLON...WELDON SPRING...
COTTLEVILLE...ST. PETERS AND HARVESTER.

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.

&&

LAT...LON 3868 9058 3868 9063 3869 9065 3868 9068
      3866 9069 3866 9093 3877 9095 3886 9057
TIME...MOT...LOC 2148Z 263DEG 34KT 3870 9083

HAIL...1.25IN
WIND...60 MPH

$$

TES
032 
WWUS53 KLSX 252203
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
503 PM CDT TUE SEP 25 2012

MOC183-252215-
/O.CON.KLSX.SV.W.0307.000000T0000Z-120925T2215Z/
ST. CHARLES MO-
503 PM CDT TUE SEP 25 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL ST.
CHARLES COUNTY UNTIL 515 PM CDT...

AT 459 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR DARDENNE
PRAIRIE...AND MOVING EAST AT 35 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...TRAINED WEATHER SPOTTERS.  SPOTTERS REPORTED QUARTER SIZE 
HAIL IN WENTZVILLE WITH THIS STORM.

IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS.

LOCATIONS IMPACTED INCLUDE...
COTTLEVILLE...WELDON SPRING...ST. PETERS AND HARVESTER.

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.

&&

LAT...LON 3868 9058 3868 9063 3869 9065 3868 9068
      3866 9069 3866 9093 3877 9095 3886 9057
TIME...MOT...LOC 2202Z 264DEG 29KT 3873 9070

HAIL...1.00IN
WIND...<50 MPH

$$

BRITT

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 25, 5:09 PM CDTSevere Thunderstorm WarningLSXSaint Charles, Saint Louis51 min
Sep 25, 5:48 PM CDTSevere Thunderstorm WarningLSXFranklin, Jefferson, Saint Louis, City of Saint Louis42 min
Sep 25, 6:16 PM CDTSevere Thunderstorm WarningLSXCallaway, Cole, Osage44 min
Sep 25, 6:22 PM CDTSevere Thunderstorm WarningLSXJefferson, Saint Louis, City of Saint Louis38 min
Sep 25, 6:45 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade45 min
Sep 25, 6:55 PM CDTSevere Thunderstorm WarningLSXFranklin, Jefferson, Saint Louis50 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.