Alert archive / Missouri / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 133, NWS St. Louis, MO

April 22, 20114 counties in Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 22, 2011, 7:11 PM CDT for 4 counties in Missouri. It was in force for 49 min. 6 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 22, 2011, 7:11 PM CDT (00:11 UTC)
Expired: Apr 22, 2011, 8:00 PM CDT
In force: 49 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 2.5 in
Wind: 50.0 mph

Counties Franklin County, MO, Gasconade County, MO, Saint Charles County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 45 km from the middle of the area, began a volume at 00:12 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 22, 7:44 PM CDT	HAIL 0.75	Union, MO
Apr 22, 7:46 PM CDT	HAIL 1.75	St. Clair, MO
Apr 22, 7:50 PM CDT	FUNNEL CLOUD	St. Clair, MO
Apr 22, 7:51 PM CDT	HAIL 1.75	Villa Ridge, MO
Apr 22, 7:56 PM CDT	TORNADO	St. Clair, MO	POSSIBLE RAIN WRAPPED TORNADO. DEBRIS OBSERVED IN FIELD OFF OF HIGHWAY 30 NEAR ST CLAIR LONEDELL CITY LIMITS
Apr 22, 8:04 PM CDT	FUNNEL CLOUD	Lonedell, MO	CROSSED OVER HIGHWAY N TOWARDS HIGHWAY 30 AND CEDER HILL

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 22, 3:34 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.2 hours before the alert went out and 285 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: 342 J/kg
Mixed-layer CIN: -152 J/kg
Mixed-layer LCL: 492 m above ground
0-6 km bulk shear: 69 kt
0-1 km storm-relative helicity: 351 m²/s²
0-3 km storm-relative helicity: 346 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

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

417 
WUUS53 KLSX 230011
SVRLSX
MOC071-073-183-219-230100-
/O.NEW.KLSX.SV.W.0133.110423T0011Z-110423T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
711 PM CDT FRI APR 22 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FRANKLIN COUNTY IN EAST CENTRAL MISSOURI...
  GASCONADE COUNTY IN EAST CENTRAL MISSOURI...
  SOUTHWESTERN ST. CHARLES COUNTY IN EAST CENTRAL MISSOURI...
  SOUTHEASTERN WARREN COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 800 PM CDT

* AT 708 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DESTRUCTIVE HAIL UP
  TO TENNIS BALL SIZE.  THIS STORM WAS LOCATED NEAR GERALD...OR 9
  MILES EAST OF OWENSVILLE...AND MOVING EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  UNION...ST. CLAIR...WASHINGTON...VILLA RIDGE...GRAY SUMMIT...
  PACIFIC...BEAUFORT...PARKWAY...MARTHASVILLE...DUTZOW...LONEDELL...
  AUGUSTA...DEFIANCE...LESLIE...NOSER MILL...LYON...PINEY PARK...
  MOSELLE...ROBERTSVILLE AND CATAWISSA.

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.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR LARGE DESTRUCTIVE HAIL CAPABLE OF PRODUCING
SIGNIFICANT DAMAGE. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 3854 9141 3865 9101 3864 9074 3829 9076
      3830 9141
TIME...MOT...LOC 0012Z 257DEG 43KT 3841 9129
WIND...HAIL <50MPH 2.50IN

$$

GLASS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 22, 7:20 PM CDT	Tornado Warning	LSX	Franklin, Gasconade, Saint Charles	40 min
Apr 22, 7:36 PM CDT	Tornado Warning	LSX	Saint Charles, Saint Louis	39 min
Apr 22, 7:44 PM CDT	Tornado Warning	LSX	Reynolds	16 min
Apr 22, 7:56 PM CDT	Tornado Warning	LSX	Franklin, Jefferson, Saint Louis	42 min
Apr 22, 7:59 PM CDT	Tornado Warning	LSX	Saint Louis, City of Saint Louis	46 min
Apr 22, 8:21 PM CDT	Tornado Warning	LSX	Jefferson, Saint Louis	39 min
Apr 22, 9:00 PM CDT	Flash Flood Warning	LSX	Franklin, Jefferson, Saint Louis	5 hr
Apr 22, 10:18 PM CDT	River Flood Warning	LSX	Jefferson	8 days
Apr 22, 10:55 PM CDT	Flash Flood Warning	LSX	Crawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more	6 hr
Apr 22, 11:10 PM CDT	River Flood Warning	LSX	Lewis	25 hr
Apr 22, 11:12 PM CDT	Tornado Warning	LSX	Iron, Madison, Sainte Genevieve, Saint Francois	37 min
Apr 22, 11:53 PM CDT	River Flood Warning	LSX	Saint Louis, City of Saint Louis	14 days
Apr 23, 1:21 AM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois	30 min
Apr 23, 1:47 AM CDT	River Flood Warning	LSX	Gasconade, Montgomery	9 days
Apr 23, 4:23 AM CDT	Flash Flood Warning	LSX	Crawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more	8 hr
Apr 23, 6:45 AM CDT	River Flood Warning	LSX	Lewis	39 hr
Apr 23, 12:29 PM CDT	Flash Flood Warning	LSX	Crawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more	6 hr
Apr 23, 4:59 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Reynolds	46 min
Apr 23, 5:27 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Washington	48 min
Apr 23, 5:41 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Franklin, Jefferson, Washington	33 min
Apr 23, 6:22 PM CDT	Flash Flood Warning	LSX	Crawford, Iron, Madison, Reynolds, Sainte Genevieve, Saint Francois and 1 more	6 hr

Nearby

Severe Thunderstorm Warnings in Missouri, 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.