Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 101, NWS St. Louis, MO

April 25, 2012Madison County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 25, 2012, 11:55 PM CDT for Madison County, Illinois. It was in force for 50 min. 5 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 25, 2012, 11:55 PM CDT (04:55 UTC)
Expired
Apr 26, 2012, 12:45 AM CDT
In force
50 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

County Madison County, IL

The radar

The St Louis radar (KLSX), 70 km from the middle of the area, began a volume at 04:55 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
Apr 26, 12:12 AM CDTHAIL 0.751 Se Carpenter, ILNICKLE SIZE HAIL 1.0 MILE SOUTHEAST OF CARPENTER ILLINOIS. VERY LITTLE WIND.
Apr 26, 12:15 AM CDTHAIL 1Marine, IL
Apr 26, 12:25 AM CDTHAIL 1.752 S Highland, IL1.0 INCH TO 1.75 INCH HAIL COVERED THE GROUND 2 MILES SOUTH OF HIGHLAND ILLINOIS. THE HAIL HAS COVERED THE GROUND AND A FOG BANK HAS DEVELOPED.
Apr 26, 12:30 AM CDTHAIL 13 S Highland, IL
Apr 26, 12:33 AM CDTHAIL 0.752 S Highland, IL

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.

IssuedProductOfficeLasted
Apr 25, 7:47 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 4.9 hours before the alert went out and 187 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 2012-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1745 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 00:00Z on 2012-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 261 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
1745 J/kg
Mixed-layer CIN
-108 J/kg
Mixed-layer LCL
1353 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
261 m²/s²
0-3 km storm-relative helicity
449 m²/s²
Significant tornado parameter
1.2
Supercell composite
4.2

Open this sounding in Storm Lab

The text

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

066 
WUUS53 KLSX 260455
SVRLSX
ILC119-260545-
/O.NEW.KLSX.SV.W.0101.120426T0455Z-120426T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1155 PM CDT WED APR 25 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MADISON COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 1245 AM CDT

* AT 1151 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR BETHALTO...
  AND MOVING SOUTHEAST AT 45 MPH.

  HAZARD...HALF DOLLAR SIZE HAIL.

  SOURCE...RADAR INDICATED.

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

* LOCATIONS IMPACTED INCLUDE...
  EDWARDSVILLE...GLEN CARBON...MARYVILLE...TROY...ROXANA...
  CARPENTER...MARINE...ST. JACOB...POAG...FRUIT AND KUHN.

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 3866 8962 3866 8994 3900 9026 3900 9001
TIME...MOT...LOC 0455Z 317DEG 40KT 3889 9002

HAIL...1.25IN
WIND...<50 MPH

$$

CVKING
1 follow-up statement
561 
WWUS53 KLSX 260511
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1211 AM CDT THU APR 26 2012

ILC119-260545-
/O.CON.KLSX.SV.W.0101.000000T0000Z-120426T0545Z/
MADISON IL-
1211 AM CDT THU APR 26 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
MADISON COUNTY UNTIL 1245 AM CDT...

AT 1209 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR MARINE...AND
MOVING SOUTHEAST AT 45 MPH.

HAZARD...HALF DOLLAR SIZE HAIL.

SOURCE...RADAR INDICATED.

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

LOCATIONS IMPACTED INCLUDE...
MARINE AND ST. JACOB.

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 3882 8995 3889 8989 3866 8962 3866 8980
TIME...MOT...LOC 0511Z 313DEG 39KT 3880 8984

HAIL...1.25IN
WIND...<50 MPH

$$

CVKING

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 25, 8:21 PM CDTSevere Thunderstorm WarningLSXAdams54 min
Apr 25, 9:13 PM CDTSevere Thunderstorm WarningLSXAdams, Brown, Pike62 min
Apr 25, 9:50 PM CDTSevere Thunderstorm WarningLSXPike40 min
Apr 25, 10:21 PM CDTSevere Thunderstorm WarningLSXGreene, Pike39 min
Apr 25, 10:53 PM CDTSevere Thunderstorm WarningLSXGreene, Jersey, Macoupin67 min
Apr 25, 11:38 PM CDTSevere Thunderstorm WarningLSXFayette37 min
Apr 25, 11:44 PM CDTSevere Thunderstorm WarningLSXBond, Madison, Montgomery46 min
Apr 26, 12:18 AM CDTSevere Thunderstorm WarningLSXClinton, Madison42 min
Apr 26, 12:45 AM CDTSevere Thunderstorm WarningLSXWashington45 min
Apr 26, 2:06 AM CDTSevere Thunderstorm WarningLSXFayette, Marion28 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.