Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 62, NWS St. Louis, MO

April 15, 2011Jefferson County, Missouri; Monroe County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 15, 2011, 4:21 PM CDT for Jefferson County, Missouri; Monroe County, Illinois. It was in force for 39 min. 2 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: Apr 15, 2011, 4:21 PM CDT (21:21 UTC)
Expired: Apr 15, 2011, 5:00 PM CDT
In force: 39 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Monroe County, IL, Jefferson County, MO

The radar

The St Louis radar (KLSX), 57 km from the middle of the area, began a volume at 21:21 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
Apr 15, 4:25 PM CDT	HAIL 0.25	3 N Hematite, MO
Apr 15, 4:28 PM CDT	HAIL 0.75	3 Sw Festus, 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.

Issued	Product	Office	Lasted
Apr 15, 12:47 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.4 hours before the alert went out and 263 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1776 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 109 m²/s²
0-3 km storm-relative helicity: 129 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.

731 
WUUS53 KLSX 152121
SVRLSX
ILC133-MOC099-152200-
/O.NEW.KLSX.SV.W.0062.110415T2121Z-110415T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
421 PM CDT FRI APR 15 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN MONROE COUNTY IN SOUTHWEST ILLINOIS...
  EASTERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 500 PM CDT

* AT 416 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
  OLYMPIAN VILLAGE...OR 6 MILES SOUTHEAST OF DE SOTO...AND MOVING
  NORTH AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  FESTUS...CRYSTAL CITY...HERCULANEUM...PEVELY...BARNHART...
  ANTONIA...WATERLOO...ARNOLD...VALMEYER...FOUNTAIN...HEMATITE...
  MAPAVILLE...CHALFIN BRIDGE...MAEYSTOWN...HARRISONVILLE...MONROE
  CITY...MADONNAVILLE...WARTBURG...FOSTER POND AND KIMMSWICK.

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 3806 9060 3848 9046 3843 9035 3839 9034
      3841 9032 3833 9015 3815 9024 3804 9043
      3803 9046
TIME...MOT...LOC 2121Z 201DEG 40KT 3814 9044
WIND...HAIL 60MPH 1.00IN

$$

GLASS

2 follow-up statements

254 
WWUS53 KLSX 152138
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
438 PM CDT FRI APR 15 2011

ILC133-MOC099-152200-
/O.CON.KLSX.SV.W.0062.000000T0000Z-110415T2200Z/
MONROE IL-JEFFERSON MO-
438 PM CDT FRI APR 15 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN
JEFFERSON AND WESTERN MONROE COUNTIES UNTIL 500 PM CDT...

AT 434 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
HERCULANEUM...MOVING NORTHEAST AT 50 MPH.

LOCATIONS IMPACTED INCLUDE...
  WATERLOO...ARNOLD...FOUNTAIN...WARTBURG...FOSTER POND AND
  KIMMSWICK.

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 3813 9040 3823 9055 3848 9046 3843 9035
      3839 9034 3841 9032 3833 9015 3815 9024
      3811 9031
TIME...MOT...LOC 2138Z 207DEG 45KT 3832 9034
WIND...HAIL 60MPH 1.00IN

$$

GLASS

952 
WWUS53 KLSX 152151
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
451 PM CDT FRI APR 15 2011

ILC133-MOC099-152202-
/O.EXP.KLSX.SV.W.0062.000000T0000Z-110415T2200Z/
MONROE IL-JEFFERSON MO-
451 PM CDT FRI APR 15 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN JEFFERSON AND
WESTERN MONROE COUNTIES WILL EXPIRE AT 500 PM CDT...

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

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 900 PM.

LAT...LON 3813 9040 3823 9055 3848 9046 3843 9035
      3839 9034 3841 9032 3833 9015 3815 9024
      3811 9031
TIME...MOT...LOC 2152Z 207DEG 45KT 3848 9024

$$

GLASS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 15, 1:09 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Pike	51 min
Apr 15, 1:53 PM CDT	Severe Thunderstorm Warning	LSX	Pike	35 min
Apr 15, 2:00 PM CDT	Severe Thunderstorm Warning	LSX	Lewis, Marion, Ralls	45 min
Apr 15, 2:20 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Saint Charles, Warren	40 min
Apr 15, 2:23 PM CDT	Severe Thunderstorm Warning	LSX	Marion, Ralls	22 min
Apr 15, 2:52 PM CDT	Severe Thunderstorm Warning	LSX	Marion, Ralls	53 min
Apr 15, 2:54 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Jefferson, Lincoln, Pike, Saint Charles, Saint Louis and 1 more	51 min
Apr 15, 3:32 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson, Saint Louis	43 min
Apr 15, 3:52 PM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Francois	38 min
Apr 15, 4:03 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis, City of Saint Louis	42 min
Apr 15, 4:43 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis, City of Saint Louis	47 min
Apr 15, 4:08 PM CDT	Severe Thunderstorm Warning	LSX	Adams	18 min
Apr 15, 4:12 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Macoupin, Pike	48 min
Apr 15, 4:13 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin	47 min
Apr 15, 4:54 PM CDT	Tornado Warning	LSX	Macoupin	38 min
Apr 15, 4:56 PM CDT	Tornado Warning	LSX	Montgomery	34 min
Apr 15, 5:10 PM CDT	Tornado Warning	LSX	Madison, Saint Clair	35 min
Apr 15, 5:37 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Marion, Washington	38 min
Apr 15, 6:05 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Montgomery	40 min
Apr 15, 6:07 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Fayette, Marion	53 min
Apr 15, 6:42 PM CDT	Severe Thunderstorm Warning	LSX	Fayette	28 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.