Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 370, NWS St. Louis, MO

June 21, 2011Jefferson County, Saint Francois County, Washington County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 21, 2011, 2:07 PM CDT for Jefferson County, Saint Francois County, Washington County, Missouri. It was in force for 53 min. 8 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, 2:07 PM CDT (19:07 UTC)
Expired
Jun 21, 2011, 3:00 PM CDT
In force
53 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Jefferson County, MO, Saint Francois County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 65 km from the middle of the area, began a volume at 19:11 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
Jun 21, 2:13 PM CDTHAIL 0.88Potosi, MOESTIMATED 50MPH WINDS.
Jun 21, 2:14 PM CDTHAIL 0.5Potosi, MO
Jun 21, 2:17 PM CDTHAIL 13 Sw Potosi, MO
Jun 21, 2:34 PM CDTTSTM WND GST 60Olympian Village, MOESTIMATED 50 TO 60 MPH WINDS.
Jun 21, 2:34 PM CDTHAIL 0.25Olympian Village, MOESTIMATED 50 TO 60 MPH WINDS.
Jun 21, 2:40 PM CDTHAIL 0.25De Soto, MO
Jun 21, 2:40 PM CDTHAIL 0.7De Soto, MO
Jun 21, 2:41 PM CDTHAIL 0.72 Se Hematite, MO

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.

IssuedProductOfficeLasted
Jun 21, 1:22 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.1 hours before the alert went out and 288 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 2011-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 489 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 2011-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -245 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
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.

487 
WUUS53 KLSX 211907
SVRLSX
MOC099-187-221-212000-
/O.NEW.KLSX.SV.W.0370.110621T1907Z-110621T2000Z/

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

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  ST. FRANCOIS COUNTY IN SOUTHEAST MISSOURI...
  EASTERN WASHINGTON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 300 PM CDT

* AT 206 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
  POTOSI...AND MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  DE SOTO...HILLSBORO...CEDAR HILL...MINERAL POINT...OLD MINES...
  OLYMPIAN VILLAGE...CADET...BLACKWELL...FLETCHER...VALLES MILL...
  MORSE MILL...VICTORIA...HEMATITE AND MAPAVILLE.

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 3836 9064 3814 9028 3779 9078 3794 9097
TIME...MOT...LOC 1908Z 225DEG 39KT 3796 9079
WIND...HAIL 60MPH 1.00IN

$$

PHILLIPSON
2 follow-up statements
081 
WWUS53 KLSX 211932
SVSLSX

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

MOC099-187-221-212000-
/O.CON.KLSX.SV.W.0370.000000T0000Z-110621T2000Z/
JEFFERSON MO-ST. FRANCOIS MO-WASHINGTON MO-
232 PM CDT TUE JUN 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN
WASHINGTON...ST. FRANCOIS AND SOUTHERN JEFFERSON COUNTIES UNTIL 300
PM CDT...

AT 229 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 DE
SOTO...MOVING NORTHEAST AT 45 MPH.

IN ADDITION...AT 217 PM...QUARTER SIZED HAIL WAS REPORTED 3 MILES 
SOUTHWEST OF POTOSI WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  HILLSBORO...OLYMPIAN VILLAGE...MORSE MILL...VICTORIA...HEMATITE AND
  MAPAVILLE.

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 3810 9084 3836 9064 3814 9028 3779 9078
TIME...MOT...LOC 1931Z 225DEG 39KT 3814 9056
WIND...HAIL 60MPH 1.00IN

$$

PHILLIPSON
270 
WWUS53 KLSX 211956
SVSLSX

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

MOC099-187-221-212006-
/O.EXP.KLSX.SV.W.0370.000000T0000Z-110621T2000Z/
JEFFERSON MO-ST. FRANCOIS MO-WASHINGTON MO-
256 PM CDT TUE JUN 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN WASHINGTON...ST.
FRANCOIS AND SOUTHERN JEFFERSON COUNTIES WILL EXPIRE AT 300 PM CDT...

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

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 800 PM.

LAT...LON 3810 9084 3836 9064 3814 9028 3779 9078
TIME...MOT...LOC 1956Z 225DEG 39KT 3833 9031

$$

PHILLIPSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 8:52 PM CDTRiver Flood WarningLSXLewis47 hr
Jun 21, 1:46 PM CDTSevere Thunderstorm WarningLSXIron, Madison, Reynolds, Sainte Genevieve, Saint Francois44 min
Jun 21, 2:44 PM CDTSevere Thunderstorm WarningLSXJefferson, Saint Louis46 min
Jun 21, 6:34 PM CDTSevere Thunderstorm WarningLSXSainte Genevieve41 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2011Every 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.