Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 280, NWS St. Louis, MO

September 7, 2012Greene County, Jersey County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Sep 7, 2012, 4:00 PM CDT for Greene County, Jersey County, Illinois. It was in force for 45 min. 2 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
Sep 7, 2012, 4:00 PM CDT (21:00 UTC)
Expired
Sep 7, 2012, 4:45 PM 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

The radar

The St Louis radar (KLSX), 66 km from the middle of the area, began a volume at 21:02 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
Sep 7, 4:11 PM CDTTSTM WND DMG2 S Carrollton, ILLARGE TREE BLOWN DOWN BLOCKING U.S. HIGHWAY 67.
Sep 7, 4:30 PM CDTHAIL 0.255 E Kane, 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
Sep 7, 2:35 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.0 hours before the alert went out and 180 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 2012-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 367 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 2012-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 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
367 J/kg
Mixed-layer CIN
-412 J/kg
Mixed-layer LCL
1436 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
102 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

547 
WUUS53 KLSX 072100
SVRLSX
ILC061-083-072145-
/O.NEW.KLSX.SV.W.0280.120907T2100Z-120907T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
400 PM CDT FRI SEP 7 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN GREENE COUNTY IN SOUTHWEST ILLINOIS...
  NORTHERN JERSEY COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 445 PM CDT

* AT 357 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED 7 MILES SOUTHWEST
  OF CARROLLTON...AND MOVING EAST AT 25 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...
  CARROLLTON...OLD KANE...GREENFIELD...KEMPER...WOODY...KANE...
  ROCKBRIDGE AND FIDELITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3913 9015 3914 9058 3936 9062 3936 9015
TIME...MOT...LOC 2100Z 272DEG 21KT 3926 9051

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

$$

TRUETT
2 follow-up statements
558 
WWUS53 KLSX 072115
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
415 PM CDT FRI SEP 7 2012

ILC061-083-072145-
/O.CON.KLSX.SV.W.0280.000000T0000Z-120907T2145Z/
JERSEY IL-GREENE IL-
415 PM CDT FRI SEP 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHERN
GREENE AND NORTHERN JERSEY COUNTIES UNTIL 445 PM CDT...

AT 411 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR CARROLLTON...
AND MOVING EAST AT 25 MPH.

HAZARD...HALF DOLLAR 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...
OLD KANE...GREENFIELD...KEMPER...KANE...ROCKBRIDGE AND FIDELITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMAIN ALERT FOR A POSSIBLE TORNADO! TORNADOES CAN DEVELOP QUICKLY
FROM SEVERE THUNDERSTORMS. IF YOU SPOT A TORNADO GO AT ONCE INTO THE
BASEMENT OR SMALL CENTRAL ROOM IN A STURDY STRUCTURE.

&&

LAT...LON 3913 9015 3914 9058 3936 9062 3936 9015
TIME...MOT...LOC 2115Z 272DEG 21KT 3926 9040

HAIL...1.25IN
WIND...60 MPH

$$

TRUETT
939 
WWUS53 KLSX 072147
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
447 PM CDT FRI SEP 7 2012

ILC061-083-072157-
/O.EXP.KLSX.SV.W.0280.000000T0000Z-120907T2145Z/
JERSEY IL-GREENE IL-
447 PM CDT FRI SEP 7 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN GREENE AND NORTHERN
JERSEY COUNTIES HAS EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 10 PM.  

LAT...LON 3913 9015 3914 9058 3936 9062 3936 9015
TIME...MOT...LOC 2115Z 272DEG 21KT 3926 9040

$$

TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 3:36 PM CDTSevere Thunderstorm WarningLSXCalhoun54 min
Sep 7, 4:11 PM CDTSevere Thunderstorm WarningLSXMonroe24 min
Sep 7, 4:32 PM CDTSevere Thunderstorm WarningLSXMacoupin43 min
Sep 7, 4:58 PM CDTSevere Thunderstorm WarningLSXSaint Clair, Washington47 min
Sep 7, 5:36 PM CDTSevere Thunderstorm WarningLSXBond, Madison, Montgomery54 min
Sep 7, 6:50 PM CDTSevere Thunderstorm WarningLSXClinton, Saint Clair, Washington40 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.