Alert archive / Missouri / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 51, NWS St. Louis, MO

March 15, 2012Saint Charles County, Missouri; Calhoun County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Mar 15, 2012, 4:46 PM CDT for Saint Charles County, Missouri; Calhoun County, Illinois. It was in force for 29 min. 3 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: Mar 15, 2012, 4:46 PM CDT (21:46 UTC)
Expired: Mar 15, 2012, 5:15 PM CDT
In force: 29 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.75 in
Wind: 50.0 mph

Counties Calhoun County, IL, Saint Charles County, MO

The radar

The St Louis radar (KLSX), 28 km from the middle of the area, began a volume at 21:49 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

Time	Report	Where	Remark
Mar 15, 4:49 PM CDT	HAIL 1.5	St. Peters, MO	AT I-70 AND HWY 79. HAIL RANGED FROM QUARTER SIZE TO PING PONG BALL SIZE.
Mar 15, 4:50 PM CDT	HAIL 0.88	St. Charles, MO	HAIL REPORTED AT 370 AND ELM STREET.
Mar 15, 4:54 PM CDT	HAIL 0.25	St. Charles, MO

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, 9.8 hours before the alert went out and 213 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1579 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 821 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 142 m²/s²
0-3 km storm-relative helicity: 117 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.

810 
WUUS53 KLSX 152146
SVRLSX
ILC013-MOC183-152215-
/O.NEW.KLSX.SV.W.0051.120315T2146Z-120315T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
446 PM CDT THU MAR 15 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CALHOUN COUNTY IN SOUTHWEST ILLINOIS...
  NORTH CENTRAL ST. CHARLES COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 515 PM CDT

* AT 444 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A SEVERE
  THUNDERSTORM PRODUCING GOLF BALL SIZE HAIL.  THIS STORM WAS LOCATED
  NEAR ST. CHARLES...AND MOVING NORTHEAST AT 30 MPH.

  AT 438 PM GOLF BALL SIZE HAIL WAS REPORTED NORTHERN RURAL ST. CHARLES
  COUNTY WITH THIS STORM.

* LOCATIONS IMPACTED INCLUDE...
  ST. CHARLES...ORCHARD FARMS...PORTAGE DES SIOUX...GOLDEN EAGLE...
  KAMPVILLE AND DEER PLAIN.

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.

THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3889 9034 3883 9036 3882 9039 3883 9044
      3879 9047 3874 9064 3882 9069 3896 9053
      3895 9052 3897 9045 3895 9037 3889 9030
TIME...MOT...LOC 2145Z 243DEG 25KT 3883 9056
WIND...HAIL <50MPH 1.75IN

$$

MILLER

2 follow-up statements

019 
WWUS53 KLSX 152155
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
455 PM CDT THU MAR 15 2012

ILC013-MOC183-152215-
/O.CON.KLSX.SV.W.0051.000000T0000Z-120315T2215Z/
CALHOUN IL-ST. CHARLES MO-
455 PM CDT THU MAR 15 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTH CENTRAL
ST. CHARLES AND SOUTHERN CALHOUN COUNTIES UNTIL 515 PM CDT...

AT 449 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A SEVERE
THUNDERSTORM PRODUCING GOLF BALL SIZE HAIL.  THIS STORM WAS LOCATED
NEAR ST. CHARLES...MOVING NORTHEAST AT 30 MPH.

IN ADDITION...AT 440 PM PING PONG BALL SIZE HAIL WAS REPORTED ACROSS THE 
NORTHERN PORTION OF O' FALLON WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  ORCHARD FARMS AND PORTAGE DES SIOUX.

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.

THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3889 9034 3883 9037 3882 9039 3883 9044
      3879 9057 3887 9062 3896 9053 3895 9052
      3897 9045 3895 9037 3889 9031
TIME...MOT...LOC 2154Z 243DEG 25KT 3886 9049
WIND...HAIL <50MPH 1.75IN

$$

MILLER

731 
WWUS53 KLSX 152210
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
510 PM CDT THU MAR 15 2012

ILC013-MOC183-152220-
/O.EXP.KLSX.SV.W.0051.000000T0000Z-120315T2215Z/
CALHOUN IL-ST. CHARLES MO-
510 PM CDT THU MAR 15 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL ST. CHARLES AND
SOUTHERN CALHOUN COUNTIES WILL EXPIRE AT 515 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

LAT...LON 3889 9034 3883 9037 3882 9039 3883 9044
      3879 9057 3887 9062 3896 9053 3895 9052
      3897 9045 3895 9037 3889 9031
TIME...MOT...LOC 2210Z 243DEG 25KT 3891 9036

$$

MILLER

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 14, 7:00 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson	45 min
Mar 15, 1:56 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Washington	49 min
Mar 15, 2:22 PM CDT	Severe Thunderstorm Warning	LSX	Crawford	19 min
Mar 15, 3:11 PM CDT	Flash Flood Warning	LSX	Crawford, Washington	3 hr
Mar 15, 3:19 PM CDT	Severe Thunderstorm Warning	LSX	Washington	26 min
Mar 15, 3:23 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Saint Charles, Warren	37 min
Mar 15, 3:27 PM CDT	Severe Thunderstorm Warning	LSX	Gasconade, Osage	48 min
Mar 15, 3:47 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Washington	19 min
Mar 15, 3:48 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Washington	42 min
Mar 15, 3:59 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Warren	46 min
Mar 15, 4:12 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis	33 min
Mar 15, 4:26 PM CDT	Flash Flood Warning	LSX	Crawford, Washington	3 hr
Mar 15, 4:50 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln	40 min
Mar 15, 5:20 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Montgomery, Warren	26 min
Mar 15, 6:16 PM CDT	Flash Flood Warning	LSX	Crawford, Washington	4 hr
Mar 14, 7:41 PM CDT	Severe Thunderstorm Warning	LSX	Monroe, Saint Clair	31 min
Mar 15, 5:17 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey	43 min
Mar 15, 5:52 PM CDT	Severe Thunderstorm Warning	LSX	Greene	38 min
Mar 15, 6:16 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin	44 min
Mar 15, 6:50 PM CDT	Severe Thunderstorm Warning	LSX	Greene, Pike	29 min
Mar 15, 6:58 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Montgomery	15 min

Nearby

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