Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 374, NWS St. Louis, MO

June 21, 20116 counties in Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 21, 2011, 4:09 PM CDT for 6 counties in Illinois. It was in force for 51 min. 10 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: Jun 21, 2011, 4:09 PM CDT (21:09 UTC)
Expired: Jun 21, 2011, 5:00 PM CDT
In force: 51 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

Counties Bond County, IL, Clinton County, IL, Fayette County, IL, Madison County, IL, Marion County, IL, Montgomery County, IL

The radar

The Evansville,IN radar (KVWX), 133 km from the middle of the area, began a volume at 21:09 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	Remark
Jun 21, 4:13 PM CDT	TSTM WND GST 75	Keyesport, IL	LARGE TREE BLOWN ONTO ROOF OF HOME...ESTIMATES THE WIND GUST WAS 70-80 MPH
Jun 21, 4:25 PM CDT	TSTM WND GST 51	Greenville, IL
Jun 21, 4:29 PM CDT	TSTM WND GST 50	Keyesport, IL
Jun 21, 4:35 PM CDT	TSTM WND GST 40	Kell, IL	PEA SIZE HAIL AND WINDS GUSTS UP TO 40 MPH
Jun 21, 4:35 PM CDT	HAIL 0.25	Kell, IL	PEA SIZE HAIL AND WINDS GUSTS UP TO 40 MPH
Jun 21, 4:40 PM CDT	TSTM WND DMG	Vandalia, IL	6 INCH DIAMETER TREE BLOWN DOWN AND 4 INCH BRANCHES BROKEN
Jun 21, 4:51 PM CDT	TSTM WND GST 52	Vandalia, IL
Jun 21, 4:58 PM CDT	HAIL 0.25	Ramsey, IL	A FEW 8 TO 10 INCH DIAMETER TREE LIMBS DOWN. HEAVY RAIN AND MINOR STREET FLOODING AT TIME OF REPORT.
Jun 21, 4:59 PM CDT	TSTM WND DMG	Greenville, IL	TREES AND POWER LINES BLOWN DOWN
Jun 21, 5:00 PM CDT	TSTM WND GST 40	Wrights Corner, 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.

Issued	Product	Office	Lasted
Jun 21, 1:22 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.2 hours before the alert went out and 147 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: 489 J/kg
Mixed-layer CIN: -145 J/kg
Mixed-layer LCL: 1353 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: -245 m²/s²
0-3 km storm-relative helicity: -164 m²/s²
Significant tornado parameter: -0.1
Supercell composite: -5.5

Open this sounding in Storm Lab

The text

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

164 
WUUS53 KLSX 212109
SVRLSX
ILC005-027-051-119-121-135-212200-
/O.NEW.KLSX.SV.W.0374.110621T2109Z-110621T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
409 PM CDT TUE JUN 21 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BOND COUNTY IN SOUTH CENTRAL ILLINOIS...
  NORTHEASTERN CLINTON COUNTY IN SOUTH CENTRAL ILLINOIS...
  FAYETTE COUNTY IN SOUTH CENTRAL ILLINOIS...
  EAST CENTRAL MADISON COUNTY IN SOUTHWEST ILLINOIS...
  MARION COUNTY IN SOUTH CENTRAL ILLINOIS...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTH CENTRAL ILLINOIS...

* UNTIL 500 PM CDT

* AT 404 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DESTRUCTIVE WINDS IN EXCESS OF 70 MPH.  THIS STORM WAS LOCATED NEAR
  CARLYLE...AND MOVING NORTHEAST AT 60 MPH.

* LOCATIONS IMPACTED INCLUDE...
  GREENVILLE...SALEM...VANDALIA...BOULDER...TAMALCO...ODIN...
  FAIRMAN...PATOKA...WOBURN...HELM...MULBERRY GROVE...SHOBONIER...VAN
  BURENSBURG...OMEGA...KINMUNDY...STEPHEN FORBES STATE PARK...
  FARINA...BROWNSTOWN...RAMSEY AND ST. ELMO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

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.

THIS STORM HAS A HISTORY OF PRODUCING DESTRUCTIVE WINDS. SEEK 
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3847 8914 3850 8915 3851 8922 3873 8970
      3935 8915 3935 8913 3922 8913 3922 8881
      3919 8880 3892 8880 3892 8869 3847 8869
TIME...MOT...LOC 2109Z 222DEG 54KT 3870 8925
WIND...HAIL 70MPH 1.00IN

$$

PHILLIPSON

2 follow-up statements

598 
WWUS53 KLSX 212136
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
436 PM CDT TUE JUN 21 2011

ILC005-027-051-119-121-135-212200-
/O.CON.KLSX.SV.W.0374.000000T0000Z-110621T2200Z/
MADISON IL-MARION IL-MONTGOMERY IL-FAYETTE IL-BOND IL-CLINTON IL-
436 PM CDT TUE JUN 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN
CLINTON...BOND...FAYETTE...SOUTHEASTERN MONTGOMERY...MARION AND EAST
CENTRAL MADISON COUNTIES UNTIL 500 PM CDT...

AT 429 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN EXCESS
OF 80 MPH.  THIS STORM WAS LOCATED 5 MILES SOUTH OF BROWNSTOWN...OR 7
MILES SOUTHEAST OF VANDALIA...MOVING NORTHEAST AT 60 MPH. PENNY SIZE
HAIL MAY ALSO ACCOMPANY THESE DAMAGING WINDS.

IN ADDITION...AT 410 PM A TRAINED SPOTTER REPORTED A LARGE TREE 
BLOWN DOWN ON TOP OF A HOME IN KEYESPORT.

LOCATIONS IMPACTED INCLUDE...
  RAMSEY...ST. ELMO...WRIGHTS CORNER...AVENA...ST. JAMES AND LA
  CLEDE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

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.

THIS STORM HAS A HISTORY OF PRODUCING WIDESPREAD WIND DAMAGE ACROSS 
PARTS OF WASHINGTON AND CLINTON COUNTIES. THIS IS AN EXTREMELY 
DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND 
STAY AWAY FROM WINDOWS.

&&

LAT...LON 3847 8914 3850 8915 3851 8922 3873 8970
      3935 8915 3935 8913 3922 8913 3922 8881
      3919 8880 3892 8880 3892 8869 3847 8869
TIME...MOT...LOC 2133Z 222DEG 54KT 3897 8894
WIND...HAIL 80MPH 0.75IN

$$

PHILLIPSON

146 
WWUS53 KLSX 212159
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
459 PM CDT TUE JUN 21 2011

ILC005-027-051-119-121-135-212209-
/O.EXP.KLSX.SV.W.0374.000000T0000Z-110621T2200Z/
MADISON IL-MARION IL-MONTGOMERY IL-FAYETTE IL-BOND IL-CLINTON IL-
459 PM CDT TUE JUN 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CLINTON...BOND...
FAYETTE...SOUTHEASTERN MONTGOMERY...MARION AND EAST CENTRAL MADISON
COUNTIES WILL EXPIRE AT 500 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.  HOWEVER GUSTY WINDS ARE STILL POSSIBLE WITH THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 800 PM.

LAT...LON 3847 8914 3850 8915 3851 8922 3873 8970
      3935 8915 3935 8913 3922 8913 3922 8881
      3919 8880 3892 8880 3892 8869 3847 8869
TIME...MOT...LOC 2159Z 222DEG 54KT 3926 8860

$$

PHILLIPSON

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 21, 2:44 PM CDT	Severe Thunderstorm Warning	LSX	Monroe, Saint Clair	46 min
Jun 21, 3:14 PM CDT	Severe Thunderstorm Warning	LSX	Monroe, Randolph, Saint Clair, Washington	46 min
Jun 21, 3:43 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Randolph, Saint Clair, Washington	47 min
Jun 21, 4:40 PM CDT	Tornado Warning	LSX	Fayette, Marion	31 min
Jun 21, 6:34 PM CDT	Severe Thunderstorm Warning	LSX	Randolph	41 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2011 Every severe thunderstorm warning in 2011

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.