Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 41, NWS St. Louis, MO

March 14, 2012Monroe County, Saint Clair County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Mar 14, 2012, 7:41 PM CDT for Monroe County, Saint Clair County, Illinois. It was in force for 31 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 14, 2012, 7:41 PM CDT (00:41 UTC)
Expired: Mar 14, 2012, 8:12 PM CDT
In force: 31 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Monroe County, IL, Saint Clair County, IL

The radar

The St Louis radar (KLSX), 59 km from the middle of the area, began a volume at 00:43 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
Mar 14, 7:48 PM CDT	HAIL 0.25	Waterloo, IL
Mar 14, 7:53 PM CDT	HAIL 1	Millstadt, IL
Mar 14, 8:11 PM CDT	HAIL 0.5	Freeburg, IL

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 00:00Z, 0.7 hours before the alert went out and 240 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: 1644 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 1773 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 86 m²/s²
0-3 km storm-relative helicity: 234 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.6

Open this sounding in Storm Lab

The text

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

871 
WUUS53 KLSX 150041
SVRLSX
ILC133-163-150130-
/O.NEW.KLSX.SV.W.0041.120315T0041Z-120315T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
741 PM CDT WED MAR 14 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN MONROE COUNTY IN SOUTHWEST ILLINOIS...
  WESTERN ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 830 PM CDT

* AT 738 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS   
  STORM WAS LOCATED NEAR WATERLOO...AND MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WATERLOO...COLUMBIA...MILLSTADT...FREEBURG...BELLEVILLE...
  SWANSEA...NEW DESIGN...SMITHTON...BURKSVILLE...NEW HANDOVER...
  BARR...FLORAVILLE AND PADERBORN.

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.

&&

LAT...LON 3820 9026 3838 9035 3843 9030 3857 8998
      3837 8983
TIME...MOT...LOC 0041Z 244DEG 17KT 3832 9021
WIND...HAIL <50MPH 1.00IN

$$

KANOFSKY

3 follow-up statements

813 
WWUS53 KLSX 150057
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
757 PM CDT WED MAR 14 2012

ILC133-163-150130-
/O.CON.KLSX.SV.W.0041.000000T0000Z-120315T0130Z/
MONROE IL-ST. CLAIR IL-
757 PM CDT WED MAR 14 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR WESTERN ST.
CLAIR AND NORTHERN MONROE COUNTIES UNTIL 830 PM CDT...

AT 753 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS 
STORM WAS LOCATED NEAR WATERLOO...MOVING NORTHEAST AT 20 MPH. 

IN ADDITION...AT 756 PM QUARTER SIZE HAIL WAS REPORTED IN MILLSTADT 
WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  MILLSTADT...FREEBURG...BELLEVILLE...SWANSEA...SMITHTON...BARR...
  FLORAVILLE AND PADERBORN.

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.

&&

LAT...LON 3822 9020 3843 9030 3843 9029 3857 8998
      3837 8983
TIME...MOT...LOC 0056Z 244DEG 17KT 3835 9013
WIND...HAIL <50MPH 1.00IN

$$

KANOFSKY

630 
WWUS53 KLSX 150108
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
808 PM CDT WED MAR 14 2012

ILC133-150117-
/O.CAN.KLSX.SV.W.0041.000000T0000Z-120315T0130Z/
MONROE IL-
808 PM CDT WED MAR 14 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN MONROE COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED ACROSS THE WARNED 
AREA.

LAT...LON 3831 9000 3831 9003 3851 9011 3857 8998
      3837 8983
TIME...MOT...LOC 0107Z 248DEG 24KT 3847 8994

$$

ILC163-150130-
/O.CON.KLSX.SV.W.0041.000000T0000Z-120315T0130Z/
ST. CLAIR IL-
808 PM CDT WED MAR 14 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL ST.
CLAIR COUNTY UNTIL 830 PM CDT...

AT 803 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED NEAR SMITHTON...OR NEAR FREEBURG...MOVING EAST AT
30 MPH.

IN ADDITION...QUARTER SIZE HAIL WAS REPORTED AT 753 PM IN MILLSTADT 
WITH THIS STORM. 

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF CENTRAL ST. CLAIR COUNTY.

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.

&&

LAT...LON 3831 9000 3831 9003 3851 9011 3857 8998
      3837 8983
TIME...MOT...LOC 0107Z 248DEG 24KT 3847 8994
WIND...HAIL <50MPH 1.00IN

$$

KANOFSKY

379 
WWUS53 KLSX 150112
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
812 PM CDT WED MAR 14 2012

ILC163-150121-
/O.CAN.KLSX.SV.W.0041.000000T0000Z-120315T0130Z/
ST. CLAIR IL-
812 PM CDT WED MAR 14 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL ST. CLAIR COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED ACROSS THE WARNED 
AREA HOWEVER SMALL HAIL IS STILL POSSIBLE.

LAT...LON 3831 9000 3831 9003 3851 9011 3857 8998
      3837 8983
TIME...MOT...LOC 0111Z 244DEG 17KT 3838 9005

$$

KANOFSKY

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	Monroe	45 min
Mar 15, 4:12 PM CDT	Severe Thunderstorm Warning	LSX	Jersey, Madison	33 min
Mar 15, 4:46 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	29 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 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.