Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 144, NWS St. Louis, MO

April 29, 2012Calhoun County, Pike County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 29, 2012, 11:51 PM CDT for Calhoun County, Pike County, Illinois. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 29, 2012, 11:51 PM CDT (04:51 UTC)
Expired
Apr 30, 2012, 12:30 AM CDT
In force
39 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Calhoun County, IL, Pike County, IL

The radar

The St Louis radar (KLSX), 88 km from the middle of the area, began a volume at 04:53 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.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 4.9 hours before the alert went out and 202 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 00:00Z on 2012-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2012-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
522 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
228 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.

068 
WUUS53 KLSX 300451
SVRLSX
ILC013-149-300530-
/O.NEW.KLSX.SV.W.0144.120430T0451Z-120430T0530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1151 PM CDT SUN APR 29 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CALHOUN COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHERN PIKE COUNTY IN WEST CENTRAL ILLINOIS...

* UNTIL 1230 AM CDT

* AT 1149 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR PIKE...AND
  MOVING NORTHEAST AT 40 MPH.

  HAZARD...QUARTER SIZE HAIL.

  SOURCE...RADAR INDICATED.

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

* LOCATIONS IMPACTED INCLUDE...
  PITTSFIELD...PLEASANT HILL...BELLEVIEW...SUMMER HILL...NEW
  HARTFORD...MARTINSBURG...NEBO...INDEPENDENCE...BEECREEK...TIME...
  PEARL...MILTON...DETROIT...BEDFORD...MONTEZUMA AND FLORENCE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DEADLY CLOUD TO GROUND
LIGHTNING. SEEK SHELTER INSIDE A WELL-BUILT STRUCTURE. STAY AWAY FROM
WINDOWS.

&&

LAT...LON 3969 9063 3963 9060 3954 9057 3946 9061
      3940 9061 3935 9062 3935 9086 3939 9093
      3941 9095 3944 9103 3947 9106 3949 9106
      3951 9108
TIME...MOT...LOC 0451Z 245DEG 36KT 3947 9094

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

$$

BRITT
2 follow-up statements
962 
WWUS53 KLSX 300502
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1202 AM CDT MON APR 30 2012

ILC013-149-300530-
/O.CON.KLSX.SV.W.0144.000000T0000Z-120430T0530Z/
PIKE IL-CALHOUN IL-
1202 AM CDT MON APR 30 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHERN
CALHOUN COUNTY IN SOUTHWEST ILLINOIS...AND SOUTHEASTERN PIKE COUNTY
IN WEST CENTRAL ILLINOIS UNTIL 1230 AM CDT...

AT 1158 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR PLEASANT
HILL...AND MOVING NORTHEAST AT 40 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

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

LOCATIONS IMPACTED INCLUDE...
PITTSFIELD...INDEPENDENCE...BEECREEK...TIME...PEARL...MILTON...
DETROIT...BEDFORD...MONTEZUMA AND FLORENCE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DEADLY CLOUD TO GROUND
LIGHTNING. SEEK SHELTER INSIDE A WELL-BUILT STRUCTURE. STAY AWAY FROM
WINDOWS.

&&

LAT...LON 3969 9063 3963 9060 3954 9057 3946 9061
      3940 9061 3935 9062 3935 9086 3939 9093
      3941 9095 3944 9103 3947 9106 3949 9106
      3951 9108
TIME...MOT...LOC 0503Z 244DEG 35KT 3951 9082

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

$$

BRITT
673 
WWUS53 KLSX 300522
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1222 AM CDT MON APR 30 2012

ILC013-149-300531-
/O.EXP.KLSX.SV.W.0144.000000T0000Z-120430T0530Z/
PIKE IL-CALHOUN IL-
1222 AM CDT MON APR 30 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CALHOUN COUNTY IN
SOUTHWEST ILLINOIS...AND SOUTHEASTERN PIKE COUNTY IN WEST CENTRAL
ILLINOIS WILL EXPIRE AT 1230 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
HOWEVER HEAVY RAIN IS STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 3969 9063 3963 9060 3954 9057 3946 9061
      3940 9061 3935 9062 3935 9086 3939 9093
      3941 9095 3944 9103 3947 9106 3949 9106
      3951 9108
TIME...MOT...LOC 0521Z 244DEG 35KT 3959 9062

$$

BRITT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 30, 4:45 AM CDTFlash Flood WarningLSXMacoupin, Montgomery6 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.