Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 464, NWS St. Louis, MO

July 12, 2011Fayette County, Montgomery County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 12, 2011, 5:10 PM CDT for Fayette County, Montgomery County, Illinois. It was in force for 30 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: Jul 12, 2011, 5:10 PM CDT (22:10 UTC)
Expired: Jul 12, 2011, 5:40 PM CDT
In force: 30 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Fayette County, IL, Montgomery County, IL

The radar

The Lincoln radar (KILX), 102 km from the middle of the area, began a volume at 22:10 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 12, 1:45 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.2 hours before the alert went out and 114 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: 1615 J/kg
Mixed-layer CIN: -167 J/kg
Mixed-layer LCL: 777 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: -14 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

779 
WUUS53 KLSX 122210
SVRLSX
ILC051-135-122300-
/O.NEW.KLSX.SV.W.0464.110712T2210Z-110712T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
510 PM CDT TUE JUL 12 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN FAYETTE COUNTY IN SOUTH CENTRAL ILLINOIS...
  EAST CENTRAL MONTGOMERY COUNTY IN SOUTH CENTRAL ILLINOIS...

* UNTIL 600 PM CDT

* AT 507 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR NOKOMIS...AND MOVING
  SOUTHEAST AT 25 MPH. NICKEL SIZE HAIL MAY ALSO ACCOMPANY THESE
  DAMAGING WINDS.

* LOCATIONS IMPACTED INCLUDE...
  NOKOMIS...WITT...RAMSEY...WENONAH...COALTON...OHLMAN...BINGHAM AND
  BAYLE CITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 3906 8920 3933 8949 3936 8945 3935 8914
      3931 8913 3922 8913 3922 8901
TIME...MOT...LOC 2210Z 314DEG 20KT 3931 8933
WIND...HAIL 60MPH 0.88IN

$$

KANOFSKY

2 follow-up statements

200 
WWUS53 KLSX 122230
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
530 PM CDT TUE JUL 12 2011

ILC051-135-122300-
/O.CON.KLSX.SV.W.0464.000000T0000Z-110712T2300Z/
MONTGOMERY IL-FAYETTE IL-
530 PM CDT TUE JUL 12 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHWESTERN
FAYETTE AND EAST CENTRAL MONTGOMERY COUNTIES UNTIL 600 PM CDT...

AT 528 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF
60 MPH.  THIS STORM WAS LOCATED NEAR NOKOMIS...MOVING SOUTHEAST AT 25
MPH. NICKEL SIZE HAIL MAY ALSO ACCOMPANY THESE DAMAGING WINDS.

LOCATIONS IMPACTED INCLUDE...
  RAMSEY...BINGHAM AND BAYLE CITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 3906 8920 3919 8934 3936 8933 3935 8914
      3931 8913 3922 8913 3922 8901
TIME...MOT...LOC 2231Z 314DEG 20KT 3923 8922
WIND...HAIL 60MPH 0.88IN

$$

KANOFSKY

294 
WWUS53 KLSX 122240
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
540 PM CDT TUE JUL 12 2011

ILC051-135-122250-
/O.CAN.KLSX.SV.W.0464.000000T0000Z-110712T2300Z/
MONTGOMERY IL-FAYETTE IL-
540 PM CDT TUE JUL 12 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN FAYETTE AND EAST
CENTRAL MONTGOMERY COUNTIES IS CANCELLED...

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.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 9 PM.

LAT...LON 3906 8920 3919 8934 3936 8933 3935 8914
      3931 8913 3922 8913 3922 8901
TIME...MOT...LOC 2240Z 314DEG 20KT 3919 8917

$$

KANOFSKY

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 12, 2:25 PM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Clair	26 min
Jul 12, 2:31 PM CDT	Flash Flood Warning	LSX	Madison, Saint Clair	3 hr
Jul 12, 3:20 PM CDT	Areal Flood Advisory	LSX	Adams	102 min
Jul 12, 3:23 PM CDT	Areal Flood Advisory	LSX	Marion, Washington	3 hr
Jul 12, 3:38 PM CDT	Severe Thunderstorm Warning	LSX	Adams, Brown	52 min
Jul 12, 3:44 PM CDT	Severe Thunderstorm Warning	LSX	Adams, Pike	46 min
Jul 12, 4:06 PM CDT	Flash Flood Warning	LSX	Marion	3 hr
Jul 12, 4:18 PM CDT	Severe Thunderstorm Warning	LSX	Marion	27 min
Jul 12, 4:31 PM CDT	Severe Thunderstorm Warning	LSX	Brown, Calhoun, Greene, Jersey, Pike	44 min
Jul 12, 4:44 PM CDT	Tornado Warning	LSX	Greene, Macoupin, Pike	46 min
Jul 12, 4:48 PM CDT	Severe Thunderstorm Warning	LSX	Marion	42 min
Jul 12, 5:03 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Macoupin, Madison, Montgomery and 1 more	57 min
Jul 12, 5:51 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Fayette, Marion	39 min
Jul 12, 6:53 PM CDT	Areal Flood Warning	LSX	Marion	4 hr

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