Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 337, NWS St. Louis, MO

October 22, 2012Greene County, Jersey County, Macoupin County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Oct 22, 2012, 9:30 AM CDT for Greene County, Jersey County, Macoupin County, Illinois. It was in force for 45 min. 1 report 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
Oct 22, 2012, 9:30 AM CDT (14:30 UTC)
Expired
Oct 22, 2012, 10:15 AM CDT
In force
45 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Greene County, IL, Jersey County, IL, Macoupin County, IL

The radar

The St Louis radar (KLSX), 75 km from the middle of the area, began a volume at 14:33 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
Oct 22, 9:31 AM CDTHAIL 0.88Jerseyville, 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 12:00Z, 2.5 hours before the alert went out and 169 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 2012-10-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 620 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 2012-10-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 103 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
620 J/kg
Mixed-layer CIN
-91 J/kg
Mixed-layer LCL
653 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
276 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.

773 
WUUS53 KLSX 221430
SVRLSX
ILC061-083-117-221515-
/O.NEW.KLSX.SV.W.0337.121022T1430Z-121022T1515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
930 AM CDT MON OCT 22 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN GREENE COUNTY IN SOUTHWEST ILLINOIS...
  JERSEY COUNTY IN SOUTHWEST ILLINOIS...
  WESTERN MACOUPIN COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 1015 AM CDT

* AT 929 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR
  JERSEYVILLE...AND MOVING NORTHEAST AT 30 MPH.

  HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED.

  IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS. MINOR TREE
           DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER BROKEN.

* LOCATIONS IMPACTED INCLUDE...
  KEMPER...SHIPMAN...GREENFIELD...FIDELITY...PIASA...MEDORA...
  ROCKBRIDGE...PLAINVIEW...CHESTERFIELD AND HETTICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3948 9006 3917 8989 3899 9040 3911 9051
TIME...MOT...LOC 1430Z 236DEG 28KT 3914 9031

HAIL...1.00IN
WIND...60 MPH

$$

BRITT
3 follow-up statements
104 
WWUS53 KLSX 221444
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
944 AM CDT MON OCT 22 2012

ILC061-083-117-221515-
/O.CON.KLSX.SV.W.0337.000000T0000Z-121022T1515Z/
JERSEY IL-MACOUPIN IL-GREENE IL-
944 AM CDT MON OCT 22 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
GREENE...WESTERN MACOUPIN AND JERSEY COUNTIES UNTIL 1015 AM CDT...

AT 942 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR KEMPER...AND
MOVING EAST AT 35 MPH.

HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

SOURCE...RADAR INDICATED.

IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS. MINOR TREE
         DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER BROKEN.

LOCATIONS IMPACTED INCLUDE...
KEMPER...GREENFIELD...SHIPMAN...PIASA...MEDORA...CHESTERFIELD...
PLAINVIEW AND HETTICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3948 9006 3917 8989 3899 9040 3911 9051
TIME...MOT...LOC 1444Z 249DEG 29KT 3917 9017

HAIL...1.00IN
WIND...60 MPH

$$

BRITT
129 
WWUS53 KLSX 221459
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
959 AM CDT MON OCT 22 2012

ILC061-083-221509-
/O.CAN.KLSX.SV.W.0337.000000T0000Z-121022T1515Z/
JERSEY IL-GREENE IL-
959 AM CDT MON OCT 22 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN GREENE AND JERSEY
COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED.

LAT...LON 3948 9006 3917 8989 3908 9014 3940 9015
TIME...MOT...LOC 1459Z 249DEG 29KT 3921 9002

$$

ILC117-221515-
/O.CON.KLSX.SV.W.0337.000000T0000Z-121022T1515Z/
MACOUPIN IL-
959 AM CDT MON OCT 22 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR WESTERN
MACOUPIN COUNTY UNTIL 1015 AM CDT...

AT 954 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED 5 MILES EAST OF
KEMPER...AND MOVING EAST AT 35 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS.

LOCATIONS IMPACTED INCLUDE...
HETTICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3948 9006 3917 8989 3908 9014 3940 9015
TIME...MOT...LOC 1459Z 249DEG 29KT 3921 9002

HAIL...1.00IN
WIND...<50 MPH

$$

BRITT
314 
WWUS53 KLSX 221510
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1010 AM CDT MON OCT 22 2012

ILC117-221520-
/O.EXP.KLSX.SV.W.0337.000000T0000Z-121022T1515Z/
MACOUPIN IL-
1010 AM CDT MON OCT 22 2012

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN MACOUPIN COUNTY WILL
EXPIRE AT 1015 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND MOVED OUT OF
THE WARNED AREA.  HOWEVER SMALL HAIL IS STILL POSSIBLE WITH THIS
THUNDERSTORM.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN ST LOUIS.

LAT...LON 3948 9006 3917 8989 3908 9014 3940 9015
TIME...MOT...LOC 1510Z 249DEG 29KT 3924 8991

$$

BRITT

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 22, 6:20 AM CDTSevere Thunderstorm WarningLSXAdams55 min
Oct 22, 6:56 AM CDTSevere Thunderstorm WarningLSXAdams, Pike49 min
Oct 22, 7:43 AM CDTSevere Thunderstorm WarningLSXPike47 min
Oct 22, 10:34 AM CDTSevere Thunderstorm WarningLSXMadison41 min
Oct 22, 11:38 AM CDTSevere Thunderstorm WarningLSXClinton, Madison, Saint Clair37 min
Oct 22, 2:04 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair24 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2012Every 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.