Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 371, NWS St. Louis, MO

June 21, 2011Jefferson County, Saint Louis County, Missouri; Monroe County, Saint Clair County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 21, 2011, 2:44 PM CDT for Jefferson County, Saint Louis County, Missouri; Monroe County, Saint Clair County, Illinois. It was in force for 46 min. 9 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: Jun 21, 2011, 2:44 PM CDT (19:44 UTC)
Expired: Jun 21, 2011, 3:30 PM CDT
In force: 46 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Monroe County, IL, Saint Clair County, IL, Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 59 km from the middle of the area, began a volume at 19:47 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
Jun 21, 2:46 PM CDT	HAIL 0.7	Festus, MO
Jun 21, 2:47 PM CDT	HAIL 0.25	Crystal City, MO	ALSO... HEAVY RAIN AND STREET FLOODING AT TIME OF REPORT.
Jun 21, 2:47 PM CDT	HAIL 0.5	Crystal City, MO
Jun 21, 2:50 PM CDT	HAIL 1	Festus, MO	HAIL RANGED FROM DIME TO QUARTER SIZE.
Jun 21, 2:57 PM CDT	TSTM WND DMG	Waterloo, IL	NUMEROUS 3 INCH DIAMTER TREE LIMBS DOWN.
Jun 21, 2:59 PM CDT	TSTM WND GST 45	Waterloo, IL
Jun 21, 3:05 PM CDT	HAIL 0.25	Waterloo, IL
Jun 21, 3:10 PM CDT	HAIL 1	2 Ene Foster Pond, IL
Jun 21, 3:29 PM CDT	TSTM WND GST 45	Freeburg, IL

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 21, 1:22 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.7 hours before the alert went out and 250 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: 489 J/kg
Mixed-layer CIN: -145 J/kg
Mixed-layer LCL: 1353 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: -245 m²/s²
0-3 km storm-relative helicity: -164 m²/s²
Significant tornado parameter: -0.1
Supercell composite: -5.5

Open this sounding in Storm Lab

The text

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

168 
WUUS53 KLSX 211944
SVRLSX
ILC133-163-MOC099-189-212030-
/O.NEW.KLSX.SV.W.0371.110621T1944Z-110621T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
244 PM CDT TUE JUN 21 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MONROE COUNTY IN SOUTHWEST ILLINOIS...
  WEST CENTRAL ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHEASTERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  SOUTHEASTERN ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 330 PM CDT

* AT 238 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  CRYSTAL CITY...AND MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  OAKVILLE...WATERLOO...COLUMBIA...DUPO...MILLSTADT...CAHOKIA...
  VALMEYER...FOUNTAIN...EAST CARONDELET...SMITHTON...MONROE CITY...
  MAEYSTOWN...MADONNAVILLE...KIMMSWICK...FOSTER POND...WARTBURG...
  BURKSVILLE...NEW HANDOVER...BARR AND PADERBORN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

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.

&&

LAT...LON 3843 8990 3804 9043 3804 9045 3822 9058
      3859 9019
TIME...MOT...LOC 1943Z 225DEG 39KT 3827 9034
WIND...HAIL 60MPH 1.00IN

$$

PHILLIPSON

2 follow-up statements

725 
WWUS53 KLSX 212001
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
301 PM CDT TUE JUN 21 2011

ILC133-163-MOC099-189-212030-
/O.CON.KLSX.SV.W.0371.000000T0000Z-110621T2030Z/
MONROE IL-ST. CLAIR IL-JEFFERSON MO-ST. LOUIS MO-
301 PM CDT TUE JUN 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
ST. LOUIS...EAST CENTRAL JEFFERSON...WEST CENTRAL ST. CLAIR AND
MONROE COUNTIES UNTIL 330 PM CDT...

AT 257 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
WATERLOO...MOVING NORTHEAST AT 45 MPH.

IN ADDITION...AT 250 PM...QUARTER SIZED HAIL WAS REPORTED IN FESTUS 
WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  DUPO...MILLSTADT...CAHOKIA...FREEBURG...EAST CARONDELET...
  SMITHTON...BARR...PADERBORN AND FLORAVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

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.

&&

LAT...LON 3843 8990 3817 9025 3816 9027 3835 9044
      3859 9019
TIME...MOT...LOC 2000Z 225DEG 39KT 3840 9017
WIND...HAIL 60MPH 1.75IN

$$

PHILLIPSON

972 
WWUS53 KLSX 212023
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
323 PM CDT TUE JUN 21 2011

ILC133-163-MOC099-189-212033-
/O.EXP.KLSX.SV.W.0371.000000T0000Z-110621T2030Z/
MONROE IL-ST. CLAIR IL-JEFFERSON MO-ST. LOUIS MO-
323 PM CDT TUE JUN 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ST. LOUIS...EAST
CENTRAL JEFFERSON...WEST CENTRAL ST. CLAIR AND MONROE COUNTIES WILL
EXPIRE AT 330 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND MOVED OUT OF
THE WARNED AREA.  HOWEVER GUSTY WINDS AND HEAVY RAIN ARE STILL
POSSIBLE WITH THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 800 PM.

LAT...LON 3843 8990 3817 9025 3816 9027 3835 9044
      3859 9019
TIME...MOT...LOC 2023Z 225DEG 39KT 3858 8994

$$

PHILLIPSON

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 20, 8:52 PM CDT	River Flood Warning	LSX	Lewis	47 hr
Jun 21, 1:46 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois	44 min
Jun 21, 2:07 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson, Saint Francois, Washington	53 min
Jun 21, 6:34 PM CDT	Severe Thunderstorm Warning	LSX	Sainte Genevieve	41 min
Jun 21, 3:14 PM CDT	Severe Thunderstorm Warning	LSX	Monroe, Randolph, Saint Clair, Washington	46 min
Jun 21, 3:43 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Randolph, Saint Clair, Washington	47 min
Jun 21, 4:09 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Fayette, Madison, Marion, Montgomery	51 min
Jun 21, 4:40 PM CDT	Tornado Warning	LSX	Fayette, Marion	31 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2011 Severe Thunderstorm Warnings in Illinois, 2011 Every severe thunderstorm warning in 2011

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.