Alert archive / Illinois / Tornado Warnings in 2011

Tornado Warning 18, NWS St. Louis, MO

April 15, 2011Montgomery County, Illinois

NWS St. Louis, MO issued this tornado warning at Apr 15, 2011, 4:56 PM CDT for Montgomery County, Illinois. It was in force for 34 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
Apr 15, 2011, 4:56 PM CDT (21:56 UTC)
Expired
Apr 15, 2011, 5:30 PM CDT
In force
34 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon

County Montgomery County, IL

The radar

The Lincoln radar (KILX), 86 km from the middle of the area, began a volume at 21:57 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 15, 5:05 PM CDTFUNNEL CLOUD4 Ene Waggoner, IL
Apr 15, 5:11 PM CDTTORNADOFarmersville, ILTORNADO ON GROUND 3 E OF I-55 AT MILE POST 70.

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 15, 12:47 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.9 hours before the alert went out and 118 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 2011-04-15Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2011-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 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
1776 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
129 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.

273 
WFUS53 KLSX 152156
TORLSX
ILC135-152230-
/O.NEW.KLSX.TO.W.0018.110415T2156Z-110415T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
456 PM CDT FRI APR 15 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN MONTGOMERY COUNTY IN SOUTH CENTRAL ILLINOIS...

* UNTIL 530 PM CDT

* AT 455 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR RAYMOND...OR 13 MILES NORTHEAST OF
  LITCHFIELD...AND MOVING NORTH AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  FARMERSVILLE...WHITE OAK AND WAGGONER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3926 8967 3950 8971 3953 8970 3953 8954
      3953 8953 3936 8953 3935 8944 3927 8944
TIME...MOT...LOC 2157Z 176DEG 26KT 3936 8956

$$

CARNEY
2 follow-up statements
725 
WWUS53 KLSX 152215
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
515 PM CDT FRI APR 15 2011

ILC135-152230-
/O.CON.KLSX.TO.W.0018.000000T0000Z-110415T2230Z/
MONTGOMERY IL-
515 PM CDT FRI APR 15 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN MONTGOMERY
COUNTY UNTIL 530 PM CDT...

AT 513 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO.  THIS
TORNADO WAS LOCATED NEAR WHITE OAK...OR 10 MILES EAST OF VIRDEN...
MOVING NORTH AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  WHITE OAK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. TAKE COVER NOW. MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID
WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE
CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3936 8953 3941 8966 3953 8969 3953 8953
TIME...MOT...LOC 2215Z 174DEG 27KT 3950 8959

$$

CARNEY
709 
WWUS53 KLSX 152227
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
527 PM CDT FRI APR 15 2011

ILC135-152237-
/O.EXP.KLSX.TO.W.0018.000000T0000Z-110415T2230Z/
MONTGOMERY IL-
527 PM CDT FRI APR 15 2011

...THE TORNADO WARNING FOR NORTHWESTERN MONTGOMERY COUNTY WILL EXPIRE
AT 530 PM CDT...

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

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 900 PM.

LAT...LON 3936 8953 3941 8966 3953 8969 3953 8953
TIME...MOT...LOC 2227Z 174DEG 27KT 3959 8960

$$

CARNEY

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 15, 1:09 PM CDTSevere Thunderstorm WarningLSXPike51 min
Apr 15, 1:53 PM CDTSevere Thunderstorm WarningLSXAdams, Pike35 min
Apr 15, 2:23 PM CDTSevere Thunderstorm WarningLSXAdams, Pike22 min
Apr 15, 2:52 PM CDTSevere Thunderstorm WarningLSXAdams, Pike53 min
Apr 15, 2:54 PM CDTSevere Thunderstorm WarningLSXCalhoun51 min
Apr 15, 4:08 PM CDTSevere Thunderstorm WarningLSXAdams18 min
Apr 15, 4:12 PM CDTSevere Thunderstorm WarningLSXCalhoun, Greene, Jersey, Macoupin, Pike48 min
Apr 15, 4:13 PM CDTSevere Thunderstorm WarningLSXMacoupin47 min
Apr 15, 4:21 PM CDTSevere Thunderstorm WarningLSXMonroe39 min
Apr 15, 4:43 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair47 min
Apr 15, 4:54 PM CDTTornado WarningLSXMacoupin38 min
Apr 15, 5:10 PM CDTTornado WarningLSXMadison, Saint Clair35 min
Apr 15, 5:37 PM CDTSevere Thunderstorm WarningLSXClinton, Marion, Washington38 min
Apr 15, 6:05 PM CDTSevere Thunderstorm WarningLSXMacoupin, Montgomery40 min
Apr 15, 6:07 PM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion53 min
Apr 15, 6:42 PM CDTSevere Thunderstorm WarningLSXFayette28 min

Nearby

Tornado Warnings in Illinois, 2011Every tornado warning in 2011Tornadoes 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.